>>280348214
This is the most explanation we ever got.

I think you just don't monsterize if you're content with yourself, so anyone emotionally stable will be fine. Note how Garou kept transforming further because he found himself against the insurmountable wall that is Saitama, frustrating him immensely.
Right now, Darkshine is the most at risk, but he seems more depressed than frustrated, and he lost his obsession with muscles, so he should be fine, too.