First Mission

A month passes as Gojo trains his physical stamina using total concentration breathing, He goes through all things that Tanjiro did when he trained in the original, He didn't use any curse energy during this training, Since that would ruin the entire point of training.

"Hmm now I can go at pretty good speeds without even using my curse energy.. Stacking my curse energy on top of my already honed physical attributes, That puts me way above then I was before. Maintaining both my curse energy and total concentration breathing can be a bit tedious though.." Says Gojo

A crow comes over to Gojo and speaks "SATORU GOJO! The master is calling upon you! SATORU GOJO!"

Gojo with a confused face.. "Wait.. crows here can speak!?"

Gojo thinks "I mean panda's could speak in my world, They probably trained this crow."

*Gojo heads towards the master's mansion*

Gojo says "Well what do you have in store for me?"

Master smiles and says "Welcome Satoru.. I have a mission for you.."

Gojo responds "A mission?"

Master says "Yes. Nearby mount Sagiri, Multiple humans have been killed by a demon.. A lot of demon slayers have also been killed while trying to slay the demon.. It seems like I would need a Hashira for this mission.. I could send a Hashira other than you but I want to see how you perform against a demon.. So I make this your first official mission, Good luck Satoru."

Gojo responds "Alright!! But wait... I am new here, I do NOT know where is Mount Sagiri.."

Master says "It is the same mountain from where Giyuu took you to this mansion."

Gojo thinks "Oh, I think I know where that is.. Alright then, I will be heading there and killing that demon."

*Gojo arrives at his destination*

Gojo looks up "The sun is about to set, I guess I will wait a bit.."

Gojo walks around with his hands in his pocket, a few minutes pass and the sun sets 

"Scanning the area from above should help" Gojo thinks as he starts to fly above

Gojo removes the blindfold from one of his eye while having the other one still covered

"Hmm..." Gojo looks around the mountain trying to find the demon

Gojo flies on top of the mountain for a while.

*Suddenly Gojo hears a loud scream*

Gojo teleports to the origin of the scream as soon as he hears it.

Gojo sees a demon girl standing in front of him who was about to devour a man.

Gojo comes in front of the demon and kicks her away, enough to send her flying away from the man

Gojo looks at the man and says "Go find a safe place to hide."

The man runs towards his house

Gojo looks at the demon's eyes.. "Lower Moon 4.. Shinobu did tell me about the 12 Kizuki, guess she is one of them."

The demon AKA Mukago thinks as she recovers from the punch from Gojo.. "Such speed and strength.. Is he a Hashira!? I need to run. I can't fight a Hashira!!"

Mukago gets up and tries to flee

Gojo thinks "Is she really trying to run..? didn't know demons can be this lame. Is she really one of the twelve Kizuki..?"

As Mukago is trying to flee, Gojo appears in front of her "Where do you think you're going?" As Gojo punches her back to the ground

Gojo says "Are you seriously gonna run? didn't know the twelve kizuki were so lame.. I thought you would be atleast somewhat strong, But you are just as weak as the other demon I fought1.. Are you atleast gonna try to fight? I mean you are gonna die either way."

Mukago who was terrified of even the mention of a Hashira, had the strongest one standing right in front of her.

Mukago screams "No.. Just please let me go!! I wanna live!!!"

Gojo says "Oh? You seriously expect me to let you go after you have ate so many humans? Also if you aren't gonna try and fight back, you leave me no choice but to just kill you instantly."

Mukago couldn't move as she lied on the ground in front of Gojo.. she thought "move.. move.. Move yourself, I don't wanna die.. no.."

Gojo says "Curse Technique Amplification: Blue!"

*Mukago explodes from within, nothing but blood of her was left*2

Gojo thinks as he puts his blindfold over his other eye again "Mannn I thought this would be some fun when I saw that she was a lower moon 4, but she was really weak unfortunately.. The other demon who wasn't even a twelve kizuki atleast tried to fight me and didn't just instantly give up after seeing me."

*Gojo makes his way back to the master's mansion with a little bit of disappointment*

Gojo says "The demon has been slayed. She was really weak.."

The master says "Satoru.. weak for you doesn't mean that it would be weak for us normal human beings"

Gojo says "Yeah I understand, By the way, it was the lower moon 4"

Master says "One of the twelve kizuki.. Good job Satoru.."

Master thinks "I have no doubt that he would easily be able to kill even the upper moon 1, Even Muzan probably..."

Gojo says "Alright I will be heading out now.."

Master nods

Gojo sleeps as he thinks about his original world again, He cared about his students and is worried about them even now.. "I will find a way.."

*The lower moon demons were called in the Infinity Castle*

All the lower moons stand in front of Muzan

Muzan Says "Lower your heads and get on your knees. Prostrate yourselves before me"

All the lower moons suddenly gets chills from just his presence and bow down.

Lower rank 3 with wide eyes: "It's Lord Muzan, I didn't recognize him!! His shapeshifting powers are mind-boggling.. Even his aura is completely different.."

Muzan Says "Mukago was killed by a new Hashira. All she thought was to run away from him. How pathetic.."

Muzan Continues "She was the waning four, I have one question to ask you all demons.. Why are you all so weak? Joining the ranks of blood moons should not be enough to satisfy you.. This is merely your starting point. To devour more humans, To obtain more power.. Your starting point for proving yourself useful to me"

"The members of the Waxing Six have remained the same for over a century, They have always been the ones to dispose off those hashira's. But what about you all? How many times you all worthless fools been replaced?"

*The demons get chills down their spines by every word muzan speaks*

Lower 6 thinks "Easy for you to say. But we.."

Muzan says ""Easy for you to say. But we?" What was it? Go ahead tell me."

Lower thinks as his eyes widen in fear "He can read our minds!? I am screwed.." 

Muzan continues "You're screwed? How exactly."

*Lower 6 Is Killed*

(Not gonna do the entire conversation here.)

*Lower 3 tries to run but gets killed*

*Lower 2 asks for blood but fails and gets killed*

*Do you two have any last words as well?* Muzan speaks as he looks at the Lower One AKA Enmu and Lower Five AKA Rui

Lower One: "Ah.. Lets see.. It almost feels like this is right out of my dreams.."

Lower Five Continues.. "The kind where we get to die by your hands in person.."

"The other demon's final breath's were like music to our ears.."

"We feel so blessed.."

"Since we just adore seeing others in despair and agony.."

Lower One: "It's like a dream come true.. We thank you dearly for making us the last ones.."

Both lower moon 1 and 5 get Muzan's blood injected in them..

Muzan Says as he smiles "That's what I like to hear.. I shall share a ample amount of my blood to you two, Although you two may not withstand it. However if you do manage to acclimate, you two will get to have a greater strength... Rui, Since there are no other Waning demons above you except Enmu, you are the Waning Two now.."

"Make yourself useful to me.. If you manage to get some information on that new Hashira, I will share even more of my blood.." Muzan Says as he dismisses both of the Lower Moons

"If we get that information from the Hashira, we will get even more blood.. Its like a dream come true.." Says the Lower Moons

A few years pass as Gojo continues to slay some normal demons when he finds them and trains his total concentration breathing further.. Nothing of much interest happens3

Tanjiro at this point, was on Mount Natagumo.

*In Master's Mansion*

Master Says to a crow "You did well to return.. So most of my children have been slaughtered..? If thats the case, There might be a blood moon there.. It seems like I have to send in some Hashira.."

Behind the master, Shinobu And Gojo were sitting..

Master "Satoru.. Shinobu... "

Gojo Says Non-Chalantly "Alright"

Shinobu Says "As you wish!"

Shinobu Says to Gojo "If only demons could get along.. Don't you agree, Satoru?"

Gojo responds "That's probably not possible.." 

Gojo suddenly remembers the incident with Tomioka "Wasn't that girl there.. A demon? She didn't devour the kid from what I remember... Hmm...."

*Both Shinobu And Gojo head towards Mount Natagumo*