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“Does it…hurt?”
Genya looks down at his hands, away from Tanjiro’s gaze. His burgundy eyes are curious, sure. But mostly they look worried. About him. As if he deserves it. He can feel the weight of that imploring stare on his skin.
He considers the question.
Does it hurt to change into a demon?
Well. It sure as hell isn’t pleasant. Starting with swallowing demon filth in the first place. Demon flesh tastes like shit rolled in ashes and seasoned with rot. He tries to not chew it if he can help it. Tries to let it slide down his throat without touching his tongue. Doesn’t matter, he tastes it all the way down.
(If there was any other way for him to be strong…for him to make a difference…for him to prove himself to Sanemi… He’d never let another bite of demon pass his lips again.)
The second it drops into his stomach, the shift starts.
He feels it spread through his veins like poison, sickly black and oily, sliding through his veins, tainting him as it goes, turning him into something wrong, something base, something inhuman. His muscles clench and his stomach convulses, trying to retch up the offending source of the poison, but he has to keep it down. He forces himself to keep it down.
If he can do that for long enough, then he starts to feel the effects he is aiming for.
His gums ache and bleed, copper tang filling his mouth as demon fangs force his blunt human teeth out of place.
His fingers feel as though someone took a hammer to them, nails dropping away in favor of black claws.
His muscles and bones burn, burn, as they grow, become denser, become harder, less breakable, with a strength that is as much a curse as it is a blessing.
His senses assault him—sounds too loud, smells too strong, lights too bright—and it makes his head feel like it is going to split until he adjusts to the change.
And he must adjust quickly.
Because while all of these changes are happening, the demon is there, somewhere, close, coming for him, going for someone else, and he has to save them—save himself—or what was this all for?
What is it all for?
Sanemi.
He clings to the picture of his brother in his mind, the last happy memory he has of him before it all went wrong: his warmth, his smile, the love he wore so openly back then.
It’s all for Sanemi.
To be strong for Sanemi. To, maybe someday, prove his worth. To get the chance to apologize. To be granted an opportunity, just once, to protect him the way that he was protected.
Big brother.
And maybe that’s what hurts the most of all.
Not knowing if it is enough. If all this is enough. If it will ever be enough.
Or if this nightmare he puts himself through is ultimately all for nothing.
“Genya?” Tanjiro asks.
Genya looks back up at Tanjiro, and he makes himself smile enough to ease his friend’s worries.
“No,” he lies, swallowing the bitterness of the truth, “It doesn’t hurt at all.”