Perhaps. But that's exactly why.

[ he looks down at her with a sad smile. even though he doesn't remember any of the lives he's taken himself, oda's aware that they'll never return to life.

those kids, too... ]

If you regret it or think about all of the what ifs it'll just...tear you apart from the inside, like a never-ending nightmare. You can't go back in time to change things. [ he sighs ] But you...can try to become a better person.