He tried to ignore the scoffing, clearly whoever had decided they were to be punished, this Lucifer, had thought it a sin so it was. That was the way it worked. Judgement and punishment. Shion wasn't pretending to understand it, there's so much he doesn't know. He can only accept what he is told, which he realises is exactly the kind of ignorance that is on his list of sins. But he's not sure how to even stop breaking that cycle.

He's distracted a moment later, a pain. A different pain than the one in his arm from where he was cut. Another slash, another shallow cut reminding him that they were not done. If it was just him he could endure, hope that he wouldn't be held forever. But the other boy lifted his shirt, he was being hurt too. Because of Shion. Because he couldn't do what he was meant to.

"I'm sorry..." He tries to keep his breathing even as he looks around for the knife, his hands are shaking so much as he picks it up and he looks at it like it is an alien object, like he has never seen one before. But he has to do this. Hurt this boy or watch this boy be hurt. It's not a choice at all.