[ Killing is something Kaneki started doing often. Out of necessity, out of hunger. Mostly the first; he eats so he can be stronger. This is the reality that was punched into him, tortured into him, shoved inside his ear. Literally.

Kaneki doesn't look back at Josuke ] Dr. Kanou... [ wait, no. There is so much Kaneki knows but there is a lot he can't really tell. Not because it's a secret, but because he simply doesn't know either. ] He knew what he was doing. He is a fucking psycho. [ it's probably the first time Josuke has heard Kaneki curse. What happened back at Kanou's lab and the things he heard Kanou say and the things he has been doing, there is no other way to describe the man as completely out of his mind.

But Dr. kanou is not important to Josuke right now. What Kaneki needs to tell the other it's about what he is, not the battles he is fighting ]

A ghoul cannot digest nutrients that didn't come from ghouls or humans. And in exchange for that, they are given pleasure at each bite of human flesh. It's difficult to explain this, but to a ghoul, that feels better than anything I have ever experienced as human. [ so it wouldn't be a surprise to Josuke to learn that some ghouls drown themselves in "food" ] But if a ghoul decides to starve themselves, hell follows. A ghoul's hunger feels worse than anything I have ever experienced as human.

With all of that, it's no wonder that a ghoul can go on hunger frenzy and hunger-driven psychosis. [ he finally looks back at Josuke ] That's what happened that day.

I had been starving myself for a month and with the Hornet's attack, I lost it.