1 Day 1

{Author's Note: Go read volume 0 if you haven't}

Tree leaves rustle gently in the wind. Crickets, hidden within the meadows, chirp continuously like a peanut gallery in a theatre as a couple of birds tweet furiously at each other. The birds rest on an enormous branch, overlooking the ground below it. The tree creeks in the wind, disturbing a young lad who laid beside it. His brown hair dances with the grass as gusts of continuous wind sweeps by.

The lad opens his eyes, neither brown, blue, or teal, but a mix of all of the colors. An indecisive iris that decided to have it all. The afternoon light reflects softly on his pupils, waking him from his slumber. The quarrelling birds are at it again, reacting to the sudden appearance of a new audience member.

'Hehe, look at that. Who knew nature could enact a soap opera?' Cain thought as he attempted to sit up.

He looks at the tree the birds are quarrelling on and notices some red spots at the base. Without his glasses he can't tell what they are, so he dismisses it, like a passing fly. He continues to search for the "actors of nature's play" and notices the tree in front of him begins to grow a little bit; its roots appear to be reaching out to him.

A sudden feeling of drowsiness overcomes him as he tries to estimate the height of this enormous tree out of curiosity. 'It's got to be at least 20 meters tall, nah, maybe 30. I don't know… I'm too tired and I can't even see the top without tilting my head all the way back.'

A fierce wind passes through the branches as the cold air pierces Cain's skin. The leaves play a lullaby as they shake for a few minutes. Before Cain has time to attempt to warm up, a tsunami of drowsiness overcomes him. With no chance to resist, he faints on the soft bed of grass, blanketed by the shadow of the overbearing tree. A sudden thud, followed by the slow creaking of the tree, as if it were trying to come to life, wakes up this somewhat average college student from his deep sleep.

Cain tries to open his eyelids tied down by the drowsiness. He manages to open them slowly, realizing that he is in the comfort of his small room. He struggles to escape the warmth of his bed, like a turtle stuck on its back. After one last push he finally escapes the clutches of his memory foam mattress. He sits on edge of his bed as he recollects that "dream."

'That was way too vivid to be a dream… It even seemed like that tree was intentionally playing music.'

A loud grumbling noise echoes throughout his room, bringing him back to the present. 'I'm too lazy to cook right now, Domino's sounds nice though.'

Cain begins to wander around his room looking for his phone. He searches his cabinet littered with shelves of tools, electronics, and textbooks right next to the head of his bed. He wanders over to his dresser, glancing over the top of the boxes stacked there. He turns to his right, staring at his closet and the boxes of snacks and drinks stashed under his shirts.

Cain bends down, prying the shirts back revealing an almost barren wall littered with small boxes and a half empty twelve pack. 'Crap, I'm running low on soda and snacks. Guess I'll need to go shopping soon.'

As he was thinking about what kinds of soda and snacks he should restock, he remembered that he was just searching for his phone a few minutes ago. He gets up and turns towards his desk, glancing over the surface until he spots it resting next to his laptop.

'You've got to be kidding me, it was behind me this whole time.' He plops down on his office chair then spins to face his desk, with his back towards his dresser. After turning his phone on, the time shines brightly in his eyes.

'Hehe, reminds me of a Spongebob meme. Wait… it's already 9pm. Guess I'm nocturnal now… Oh well, time to order some pizzas.' After navigating the Domino's app and ordering two pizzas, Cain logs into his laptop, greeted by his homework that was due last night.

'Welp, it's too late to turn this in now. Might as well check what assignments are due this week while I'm here. Let's see… Two for Thermodynamics, one for Solid Mechanics, one for Dynamics, one for Math Methods for Engineers, a quiz for Intro to Aerospace Engineering, and a lab summary for Physics. Ugh… How hard is it to have a carefree life? Meh, I'll just do it tomorrow, procrastination for the win.

'Now, how should I pass the time? Guess I'll check to see if any of the mangas I read have updated yet.' He habitually navigates to the folder that contains all of the mangas he is currently reading, located on Google Chrome's bookmarks bar and opens all of the websites at once.

After speeding through 219 different websites, closing the ones that have yet to update, 41 tabs remain open. He reads through 10 chapters before glancing at his phone. A notification pops up stating the delivery driver is at the door.

Cain rushes out his room, sliding on the wooden surface that paves the way to the front door, arriving seconds before the doorbell rings. 'Safe! I should be careful since my housemates are probably sleeping.'

After receiving the pizza, he slides to the fridge and tucks one of the boxes inside the almost overflowing shelves. The sound of a door opening and closing startles him, and he rushes back into his room with the remaining box of pizza.

'Phew that was close. It's too soon for human contact. I haven't even had my morn- er, nightly liter of soda yet. Hehe, introvert life ftw.' Cain begins to open the pizza box and gets settled in while he starts to devour the food. After reading the remaining chapters on the 31 tabs and finishing the pizza, he cleans up a little bit then unconsciously wanders to his bed.

'Oh, I'm in my bed… Mine as well take a nap while I'm here. I wonder if I'll see that tree again. Eh, it's not like it's real or anything. That would be nice though, it seemed like I could have a lot of freedom over there. Reminds me of something I just read, "Those who are truly free are not afraid of being controlled nor are they slaves to their own desires," or something like that. Life advice from manga, nice.' Cain's thoughts begin to trail off as the familiar sense of drowsiness washes over him and he eventually loses consciousness.

Crisp sunlight slowly creeps over Cain's eyes as he begins to wake up. 'Oi, who turned the lights on?!'

As he unwillingly wakes up, he feels something soft under his head. It doesn't have the same texture as his pillow and is softer. The surface is very smooth, with some odd rough patches here and there. As he opens his eyes, he sees two beautiful mountain peaks with the sun peeking between the small space between them.

'Wait… These aren't mountains. Factor in the sense of this pillow… Pillow? No this is definitely a lap, then that must mean that those are-' As he begins to realize that he has been laying on the rumored lap pillow, a soft voice breaks his thoughts. "Master, are you awake now?"

The sudden voice startled Cain and he immediately leapt a little less than a meter forward, the peaks of the mountains brushing his bed head slightly. He looks at the source of the voice, seconds before it speaks again in a playful manner. "Master, that tickled."

Cain was completely stunned at this unimaginable sight, a sight that he never thought he would be able to see. A beautiful naked lady was sitting perched on the grass, the same grass that was in his dream. As he looks at his surroundings, he notices that the giant tree has disappeared.

'Impossible… It's not like it grew legs and walked away right? Wait…' As he looks back at the young lady, he looks over her body once more.

Not in the way a husband would look at his wife, nor in the way teenage boys would peek at the girl's changing room. This gaze was akin to a scientist examining his research subject, picking up on every small detail, filled with curiosity. Well, every detail that wasn't blurred.

'Dang it, I don't have my glasses on. All I can make out is her basic shape and some details.' As he begins to try and make out the details of this mysterious lady, he notices that the rough patches of "skin" were actually small patches of bark. Her forest green hair reached below her waist, piled up behind her. The lady's light green eyes stared at Cain, almost as if grassy plains were looking back at him. Her delicate white skin glistens in the sunlight, creating a huge contrast between it and the bark patches. After a few minutes of awkward silence, Cain finally speaks up nervously.

"Why are you naked?"

The lady replied, "Because I just evolved."

"So you were that giant tree before?"

"Yes and no. I am what humans call a 'Whomping Willow.'"

'Woah, isn't that from Harry Otter? Don't these types of trees attack everything in sight? Why am I unharmed?' Numerous questions began to flood Cain's mind.

A few minutes pass of Cain thinking over the current situation before he asks, "Why do you call me 'Master'?" The mysterious lady looks at Cain, then quickly averts her eyes.

'Why is she being shy all of sudden… It's not like she did something bad right? Maybe she's embarrassed, but she doesn't seem to think anything is wrong about being naked. Weird… Women are hard to understand. Wait, would she be considered a woman?' As Cain starts to question her odd behavior, the mysterious lady looks up at Cain nervously. She hesitates for a little bit then begins to explain.

"For my species, we require the mana of living things to grow stronger. I usually draw some mana from passing adventures as they rest in my shade. Not enough to drain them completely, but about half of their mana is used as 'rent,' as Master would say."

The lady seems oddly proud while saying this, like a child showing their parents something they've created. Before Cain has a chance to question the oddity of her last statement, she continues.

"While I was taking Master's mana, I realized that Master wasn't recovering any of it, unlike the adventures beforehand. By the time I noticed something was wrong, I had already taken a little more than half of Master's mana. Mana is considered a lifeline for adventurers, so I would like to protect the Master as payment for the mana Master permanently lost." As she finishes her sentence her voice wavers with a mix of fear, concern, and worry.

Cain gets up and starts to pace as he thinks over what she just said. 'Woah, a so-called monster that seems to be a pacifist? Wait, if there's mana then that means there is magic. Assuming this isn't a dream, what was the dream I had before I got pizza? Why would I have that dream but still be able to order pizza and spend time in my world?

'Wait, none of this matters right now. If this isn't a dream, then that means I have limited mana. Based on the manga I have read up until now, this is definitely not a good thing. In other words, this lady is assuming responsibility by becoming my servant? But just how much did she take? How much do I have left? Also, what did she mean by "as I would say"?'

Countless questions swarm Cain once again until he gets a splitting headache. 'Eeergghhh. Breathe… First, I need to see how much mana is left and if there is a way to get it back. Figuring out how magic works in this world will be my lifeline according to her. Next is to question her about that oddity in her statement. Her… Wait, what's her name?'

Cain looks over at the mysterious women. The woman tilts her head a little bit and stares back confused. She's like a mix between a dog and a child… After a brief staring contest, Cain asks for her name.

She replies in a serious, flat tone and a blank face, "Adventures usually call me 'demon' or 'monster.'"

'This isn't going to work, how innocent can she be? Does she not understand the meaning of those words? Choosing a name isn't a simple matter either. I suck at coming up with names too. Let's see… she was a giant tree before, so this should work.' After a short inner debate of the name, Cain hesitantly states "I'll call you Yggdrasil, Dresil for short."

Upon receiving her new name, Dresil's eyes lit up as if she were a child that was just given ice cream.

'Dang she's too cute. She looks around 20 or so too. Well, I guess a human's sense of age doesn't apply to monsters. At least she liked it, I wonder what would have happened if she didn't.'

Flashes of him dangling from a branch in the air or being swung around violently like a kid zooming on a merry-go-round appear in his mind. 'On second thought… let's not do that.' As Cain begins to be lost in thought he notices the bark patches on Dresil are slowly spreading. He looks at her concerned and gestures to a patch of bark on her leg. "What's happening?"

Dresil looks away embarrassed. "I… I stopped taking Master's mana before I finished evolving so Master wouldn't lose too much."

Cain looks at her shocked. "What happens if you don't finish evolving?"

Dresil avoids Cain's gaze as he tries to look her in the eyes. "If I don't absorb mana within a day, I'll slowly start to become a tree over the next few years. Once I become a tree, I'll lose all consciousness and wither."

Cain stares at the grass feeling guilty. 'She doesn't seem to have lied at all, nor does she have any malice. I just thought she was forcing herself to become my servant, but it looks like it was out of concern for me not being able to use mana for long, despite limiting her lifespan. She probably thinks she's the reason why I can't recover mana.

'Based on what Dresil said about the adventures who came here to rest, that doesn't seem to be the case. There's also the slim chance she was forced to do all of this… Let's shelf that for now; more importantly, I still need to ask her about my mana. Man… I need to fix this dumb short-term memory.'

Cain moves closer to Dresil and sits in front of her. Dresil becomes anxious with each increasing second. To her knowledge, if something similar were to happen to other adventures, they would beat the person responsible and make them pay back with everything they had. Losing the ability to use mana is worse than not having food after all. Compared to those circumstances, being a servant for a few years is nothing.

Cain attempts to get Dresil to look at him before speaking up. "How much mana do I have left, how much did I start with, and how much do you need to finish evolving? In numbers if possible."

Dresil quivers in fear of being hit as he speaks. A few seconds pass by before she slowly looks up at Cain. Cain stares in silence, expecting an answer. Relieved that he doesn't seem to blame her for his situation, she responds immediately.

"I took about 17 million from you. From what I could sense in the Master's body, there were about 30 million floating inside. There were no magic circles surrounding the Master's heart. I need about 10 million more to finish evolving."

After some mental math, Cain calculates he will have about 3 million mana left after treating her, and 13 million right now. 'Wait, I don't even know how much this is. It's like having 20 kilograms of steak but not knowing how much kg a person usually eats in a day. Time to find out everything I can about this world. Kinda wish I had a lamp… Oooh this twig should do.'

Cain picks up a small twig that was lying beside him and hovers it in between their heads. With the ends pointing towards Dresil, he begins a barrage of questions using the countless fantasy knowledge built up from reading mangas and watching anime/tv.

"Explain the current system of ranking for mana, what a magic circle is, and what you meant by 'as I would say'. Are there any elemental properties to mana? What are the different types of elements? What elements can I use? How much does this world depend on mana? How are spells cast? Can mana be used to create objects? According to your knowledge, what are the levels or ranks of the strongest people on this continent? Where did you get this knowledge from? Why can I understand the language you're speaking, are you speaking English?"

Cain lifts his head proudly as his successful barrage of questions is also a reference to a meme. 'I've always wanted to do that. Who knew all of that information from the fantasy manga would come in handy like this?' Dresil stares back blankly, his attempt to lighten the awkward mood succeeded, but not in the way he had hoped.

"Master, you're not a detective and that isn't a lamp…" Disappointed, Cain puts the stick back down. 'Awww, she's no fun. Wait, just how did she-' Before Cain could finish his thoughts, Dresil continues.

"When adventures rest here, I usually stick my roots into the base of their skull and use my mana to pick out information. This harmless operation helps me stay one step ahead of the Adventurer's Guild so I can change locations before they send adventures to hunt me. I am outside the Hellion Forest after all. It would be strange if people didn't find a lone tree out in these meadows suspicious.

"After Master appeared suddenly and slowly phased out, I was curious and waited to see if Master would come back. An hour or so later, the Master phased slowly back onto the grass. I used this chance to investigate why you kept appearing out of thin air. While looking through Master's memories, I learned the English language and that you were from a different world."

Dresil pauses to push up imaginary glasses while proudly saying, "Only one truth prevails!"

'Did she just make a Con*n reference? I hope part of my personality didn't get imprinted onto her. She did say she looked through my memories. Depending how that info is assimilated, it can be the same as copying someone's personality or merely reading articles. Understanding what she saw is also different from knowing it.

'Wait, did she even see all of my embarrassing moments too?' Cain's face begins to blush as he recalls countless moments in which he did stupid things. Dresil looks at Cain and guesses what's happening. She decides the best thing to do is to not let his thoughts run around and quickly resumes her explanation.

"As for everything pertaining to mana… According to the adventures that came by over the decades, the average person has about 10,000 mana and can be considered a one circle mage. After every additional circle, the amount of mana that can be stored doubles. A second circle mage can store 20,000, a third circle can store 40,000, and so on.

"The ranks for adventures are divided into D, C, B, A, and S rank. You need to be at least a second circle mage for a D rank, a third circle mage for C rank, etc. In order to promote, you have to complete 5 requests higher than your current rank with no more than 4 other people helping. One to three people can use the quest to rank up and a party's rank is determined by the average rank of the members, unless proven otherwise using the previous method.

"There is a way to promote without these requirements by directly challenging a guild official. If you beat that official, you get promoted to that official's rank and the fee is waived. However, if you lose, you have to pay the guild 100 gold, or about $10,000 for damages, registration, and wasting time (the fee). The guild officials are in the top 10 of every rank so this method is rarely used.

"The strongest person on this side of the forest should be an 8th circle mage who is currently at a mage tower researching, although most adventurers are only at the 4th circle. I learned this from a party of adventures a few days ago."

Dresil stops for a moment to take a breath and looks at Cain expecting praise. 'She really is like a child…' A few moments of silence pass and Dresil pouts while looking away. Disappointed, she continues with her lecture.

"There are seven known basic elements. Fire, water, earth, air, light, dark, and spiritual. The first six are the same elements that Master is familiar with. The spiritual element refers to one's ability to summon spirits from another dimension.

"For every element there exists a type of corresponding spirit. Instead of the spiritual element, there is a space spirit. Although, it has been thousands of years since one was summoned and is now considered an urban myth.

"The spirits follow the same rank as adventures, with the exception of SS and SSS rank spirits. SSS rank spirits are known as 'Spirit Kings' and rule over their corresponding elements. The last time one was summoned was over a hundred years ago; all of the spirits under its rule were unable to attack the King's summoner despite their summoner's order.

"Spirits stay in this world by using their summoner's mana. Any spirit at S rank or above requires the flesh of the summoner to be sacrificed. According to Master's memories and scientific deduction processes, the flesh is most likely used to stabilize the power of said spirits."

'This girl… Just how much of my memories did she see?' Dresil looks at Cain expectantly. Cain reluctantly says, "Good job, that's one of the hypotheses I would've come across." Dresil's eyes light up again.

'Ay, she turned on the high beams.' Cain thinks to himself, blinded by her happiness. After basking in her moment of glory, Dresil picks up where she left off.

"All mana, except natural mana, contains elemental properties. Humans can have any element. Elves commonly have earth, air, and high spiritual talent. Dwarves usually have fire, earth, and most are able to utilize an advanced form of earth: metal.

"For each basic element, there is an advanced form. As long as one has a decent understanding of the basic element, enough mana, and some understanding of the advanced element, they can cast spells of that advanced element.

"Once again, the elements are fire, water, earth, air, light, dark, and spiritual. Their advanced forms are lightning, ice, metal, sound, holy, and demonic. The spiritual element isn't really a type of element, but a type of talent or affinity.

"Generally, only spirits that share the same element with their summoner can be summoned. For example, an adventurer with fire and air can only summon those two spirits, unless they have an understanding of another element and high spiritual talent.

"The holy and demonic elements appear to be bestowed by the gods or demons to those with high talent for the respective elements. Different advanced elements can be created by combining different elements.

"For example, mixing fire and earth creates lava. In order to use this type of element, decent control over mana and complete understanding or talent of the basics is required. Based on rumors, one can overcome the need to understand with an absurd amount of elemental mana.

"When natural mana is absorbed, it is converted to the elemental mana that the person has inside their body. People with no elements are rare and are considered to be trash. It is also rare for conflicting elements to be inside one person.

"When this happens, there is a violent collision between the two different types of mana as they attempt to dominate each other. The person won't live long due to the backlash unless something intervenes."

As she says this last bit, Dresil looks down again, trying to avoid a certain topic. Cain, not aware of his surroundings, begins to parse through this immense amount of information.

'Dresil is getting better at predicting what questions I may have and answering them ahead of time. Guess she doesn't want another barrage of questions…

'So basically, the more understanding of an element you have, the more you can use it. And even without understanding the element you can just brute force it with mana. In other words, aren't I overpowered? I have enough mana after treating Dresil to be on par with an 9th circle mage and great understanding of all elements due to my engineering courses and manga.

'Wait... if you treat mana as an energy source, then natural mana, and maybe non-elemental mages, can derive every element from the elementless mana. Well, I guess others can't since they don't have enough understanding of the elements or science to realize this?

'But aren't elements just a certain arrangement of molecules and internal energy? Then why are there different types of elements that exist and cannot be changed in someone's body? Is it determined by the DNA, and just like the method for reproducing cells is located in the cell, is natural mana converted by the elemental mana existing in the body?

'I should probably stop trying to discover the laws of mana and just enjoy the fact that if this isn't a dream, there's a chance I get to see some real elves.'

Dresil waits patiently as Cain digests all of the information. Once Cain looks up at her, she interprets it as the signal to continue.

"Spells are usually cast by chanting and a magic circle, silent casting and a magic circle, or visualization with no magic circle. If the chant is altered, the spell will also be altered in different ways. The last method is one recorded in the legends and hasn't been seen for a while. As for magic involving the creation of objects, apart from illusions, it's just a myth.

"Magic is used in everything from helping with chores to destroying cities. Mana is used in every typical RPG class, even fighters who use their fist. As for the Master's elemental body and magic circle… you have none of either. I'm afraid you won't be able to do much in the future. Just rely on me!"

'Why did she remind me of a dog when she just said that last bit? Ah, whatever… I guess she didn't copy my personality and point of view, otherwise she would understand that trash elements (or non-elements) don't exist, only people who don't understand how to use it or understand it in general. In other words, an elementless body should mean being able to use every element.

'As for the creation of objects… I wonder if I can use mana to force the right conditions of E=mc² to take effect. If mana is really an energy source, then it should work. But how many joules of energy are in a single unit of mana?

'From what Dresil said, magic circles are like a preset for spells. Does this mean I can create magic circles and program them to do different things?'

Before Cain could ask Dresil more questions, Dresil pointed at the horizon. Cain looked over his shoulder and saw a vast, dark forest. It was shrouded in an eerie mist, with several beaten paths leading into it.

This wasn't what Dresil was pointing towards though. When Cain looked on top of the trees, he realized the sun was setting. The setting sun combined with the sudden feeling of hunger, reminded Cain of an unbearable pain.

'I didn't get to eat that last pizza!!!' His solemn cry of frustration is interrupted by a gentle prodding on his side. He looks back and sees the naked Dresil offering an apple.

'Why does this scene look familiar? Oh well, free food. Wait, she's still naked!' Cain quickly pulls off his shirt and hands it to Dresil while grabbing the apple. "Put this on." Cain says looking away in shame, attempting to distract himself by eating. Dresil struggles to put the shirt on due to the stiffness of some areas on her body. When the shirt is finally forced on Cain looks back. 'Dang it, this just looks sexier. Like the morning after with your wife.'

After staring at Dresil once more, he remembers the issue about her evolution. Cain stretches out his hand, "Take the mana you need, I would rather you be healthy than having an extra 10 million of mana."

Dresil looks at him, blushing slightly. 'I never knew humans could be so kind to monsters,' she thought.

"Sit behind me and put your hand on the patch of bark on my back, I'll do the rest Master." As Dresil instructs Cain, he notices the size of the mountains once more.

'Dang you can even see them from behind. They've got to be at least an E cup. Wait no focus…' Cain lifts up her shirt nervously and gently places his hand on the massive, rough brown patch on Dresil's back.

'Man, this is too much stimulation for a shut-in like me. I was fine earlier because I was preoccupied with the knowledge of this world. Now I can even feel her heartbeat. Wait, she has a heartbeat? Dang, this place is so mysterious… So many experiments that need to be performed!'

As Cain thinks over the potential experiments, his hand slowly sinks into Dresil's back. When he looks at it, it reminds him of a rippling lake that was once still. Vines stretch out from where his hands once were and wrap around his arms. Once they are tightly fastened, Cain feels endless amounts of mana being drawn from him, as well as the waves of drowsiness washing over him.

'Isn't this what I felt before when I came here? Come to think of it, Dresil said I kept phasing in and out. Did the summon fail or something? That could explain my abnormal amount of mana, a glitch in the system.'

While Cain was simulating the different possibilities, an important question came into his mind. "Dresil, was there anything wrong with my body when you were absorbing my mana the first time? Any drops in my vitals, cellular abnormalities, implants or something that might force me to be compliant towards someone, etc."

Dresil slows the mana drain as she starts to respond. "None of that, Master. Apart from the weird phasing everything was normal." She picks the pace back up as Cain begins to find a solution for his case.

'Interesting… This means that this body can hold 30 million mana with no difficulties. If I make a dedicated organ and pathways for controlling my mana, I won't have to keep strengthening my heart and veins. After all, the 30 million wasn't concentrated in one spot before, it was just… existing…

'There's also no guarantee I can use mana to strengthen my body permanently to withstand continuous use of casting. If that were possible, I would assume there would be more 8th and 9th circle mages, since strengthening magic exists (for the fighters and such). I can just use mana to carve the pathways and use my body as a vessel.' As Cain was sorting out the specifics to his mana circuit, he slowly drifted to sleep.

{Author's Note: Discord link; https://discord.gg/gTWs4fmGfM. Join to share theories and discuss. All theories will be confirmed or denied, all correct ones have rewards.

The reward is an answer to any question about the story. Keep in mind, I won't care about spoilers while answering these bois (since it's a reward). So if someone asks "What is the plot surrounding Cain's summon?" I will explain everything w/o leaving details behind, or just do a detailed summary (depending on how long the boi is). }