Cooperation

"I'm a demon..."

The silver-haired guy said that. If true, he should be the enemy I must defeat. But. 

"Oh, how surprising."

Those words left my mouth. Even I'm surprised.

I had things I wanted to ask, like why he was in a human tavern and what he's thinking. But more than that, I was intrigued by his offer of cooperation.

"Ahaha, you don't look too surprised. But it's true. I'm a demon, the demon king's son, commander of that fortress you'll attack." 

Is that so? The king's own son? Now I really am surprised.

"Hmm. So what's this cooperation?"

"I didn't expect such a calm reaction after revealing my identity." 

I'm surprised. Scared witless. Take a good look at my trembling knees. Laughing, aren't you?

But for some reason, I felt something would happen. No, something would change.

"May I first ask your name?"

"Engy."

"Okay, Engy-san. About cooperation...will you die with me?"

...

"Something's off about this fortress, don't you think?"

"Yeah, where is everyone?"

The day after meeting the self-proclaimed demon king's son, the esteemed hero party stormed the fortress. 

I was only half convinced about what Roots said, but having an idea about the situation, I pondered alone.—No way, really? If so then...

Thinking ahead, I naturally smile.

"Ha."

"What's with this guy? Has he gone mad? Like this, he's only good as a shield for us."

"I think Engy is better as a baggage carrier than a shield."

"Should we knock him out?"

I'm some old TV? Their attitudes are the same as ever. 

But today's me is different. No matter what they say, I won't waver.

"It's fine, fine. Make me a decoy or shield or whatever. Use me however you want. You can't replace me after all."

The me speaking unthinkable things for normal me was there. 

"My, how principled. Do you finally understand your position?"

"Engy, that's no good. If you do that, who'll be the baggage boy from now on?"

"AT Field."

Amidst that exchange, we arrive at the fortress depths. There Roots sat alone on a chair, watching us.

He must have been holding back. Unlike yesterday, his intimidation was on a different level.

"What's with that guy... What is he..."

"Engy, stay out of the way! Keep quiet in the corner!"

"Yeah."

The heroes seem more nervous than ever. 

Even sleepy-eyed Lettie is focused, eyes wide open.

As told, I withdraw a bit.

"You came." 

"Just you? Where are the other troops?"

"It's just me. I had everyone leave the fortress. I don't want to wastefully reduce our forces fighting you."

"What does that—"

"I alone am enough!"

Roots assaults the heroes, still not comprehending.

The heroes try to respond, but his power was a step above.

Spitzy at the vanguard can't land a single wound, while only accumulating injuries herself. 

Even Melt's magic, said to be the strongest in Balm Kuchen Kingdom, inflicts little damage.

Thanks to Lettie's recovery magic, they somehow avoid fatal blows and keep fighting, but not for much longer.

"Is this it? Some heroes you are! I'll finish you in one blow!"

"Ah!"

Seeing Spitzy brought to her knees, Roots unleashes a massive spell.

Judging it hard to evade, Spitzy closes her eyes tight and crosses her arms before her face.

A moment of silence. Then a shadow leaped forth.

"Tch... damn..."

It was me. I shielded Spitzy as declared. 

It's much worse than I expected. Aside from pain all over, blood drips steadily to the floor.

Above all, my right eye saw nothing anymore. 

"How is it? Good shield, right? Though it's of no use anymore."

"You, why—"

"Engy!"

Seeing me, Spitzy looks shaken.—Heh, feels kinda nice.

I smile thinly and look to Roots before me. Roots has his eyes wide, flustered.

Sorry. This wasn't the plan, right? I don't know why I moved either. My body reacted on its own. 

They didn't treat me that well, but we spent a long time together. Maybe I got a little emotional.

Not like me. As I ponder the reason in the corner of my mind, I meet Roots' gaze. 

The plan differed a bit, but work with me from here on.

"Stay back! I'll take this guy down!"

Noticing the other two approaching from my side vision, I stop them.

"Engy? You can't, you're..." 

"Sorry Melt. I kept it hidden. The special heroic power not on that appraisal." 

"Huh?"

"It goes like this!"

Clinging tightly to Roots so he can't get away, I unleash all my magical power. A flashy spell, making it seem like self-destruction. 

Seeing that, Roots smiles and activates some magic.

With a deafening roar and huge explosion, Roots and I vanish from the fortress without a trace.

...

"Complete success!" 

On the outskirts of the town nearest the fortress.

Hands on my hips, I speak cheerfully. 

"What's a success? I didn't agree to that!"

Before me is a pathetic guy, fretting.

Nothing of the mighty being from earlier can be felt now.

We were supposed to have died here. That was our agreement. 

With that, we've both gained freedom. A great success, right?

"It went well, though different from the plan. Good, isn't it?"

"No good at all! Engy-san, you should take a look at yourself. It's really bad."

Seriously? It hurt a lot, but that much?

I'm standing normally though. My eyes are...recoverable with magic, right? You can fix it, right?

"Engyyyyy!"

Phoenix joins us. Realizing the plan succeeded, he came flying.

I had Phoenix wait outside the fortress in case Roots' claims of being the demon king's son were lies, to ensure an escape.

But Roots' power exceeded expectations. If we'd opposed him unknowing, we would've been...without even a chance to flee.

"Yo." 

"Oh no! Who's this blood-soaked man? Where's Engy?"

Huh, blood-soaked? What happened to me?

As Phoenix looks around in confusion, I speak up.

"It's me, Engy. Just went through a slight image change."

"Hah? Engy? More than image change, your looks are monstrous now. Some undead type, feels familiar."

I think it's just appearance, but his harsh words make me uneasy. I have Roots cast recovery magic on me.

The pain vanishes, but my eyes apparently can't be fixed.

"Sorry, I didn't mean to..."

"It's because I jumped out. Don't worry about it. As long as I've got one eye, it'll work out somehow." 

"Engy, I'll be your eye from now on. I'll see in your place for what's to come."

Despite me saying it's my own fault, Roots looks at me with moist eyes, unable to forgive himself. 

He said he's a man, but he's kinda cute. Not that I swing that way.

And Phoenix, I've still got one eye, you know? You just wanted to say a cool line.

"I didn't intend to go that far..." 

The magic's power shows he likely didn't plan to kill me. Hearing my talk yesterday, he probably empathized.

"Thanks to you, I got to see that woman falter. I'm personally quite satisfied."

"I know! Let's swap my eye with Engy-san's!" 

"Huh? No thanks."

Roots suddenly suggests something scary. That'd be a huge incident in Japan.

"Please, let me do it. I'm grateful to you, Engy-san. Probably much more than you think."

"Well, I'm scared of casually swapping eyes. Besides, if we could even do that, wouldn't you lose sight then?"

"It's fine! Despite appearances, I'm a high-ranking demon. My body will gradually regenerate, even if I can't see for a while. And since I'll handle the swap with magic, it won't hurt at all! Don't worry! Please, let me do it!"

When he pleads with that face, I somehow can't refuse. But hmm...

Defenseless as I pondered something stupid, he draws near. 

"Thank you, leave it to me. Engy-san, just stay still. I'll finish quickly."

The moment I hear those words, my body is bound by magic.

Not just staying still, I can't move at all. And why is my mouth blocked too? Is that necessary?

And what's with the "thank you"? I never agreed to this.

After that, it happens fast. 

Pop, float, plop into Roots's hand. 

Then Roots' right eye follows the same process, removed and swapped into my eye socket.

I feel a warm sensation, then my vision returns.