...Trust me, I know. Even if it might have helped someone in the end, it doesn't erase the feeling of killing someone else. It never will.

[ this is unusually soemn, for kazunari. ]

The only thing you can do is remember that you did it to help someone, not out of cruelty, and try to find something to keep you going. Which you must have, right? It's not like you to give up.