okay so i think i know why steven was super fuckin pissed in this episode.
normally when facing a foe, steven never jumps to anger. he always tries to take the most peaceful route. he’s always tried to be a forgiving pacifist. but with all his past enemies, he’s only known how they had hurt him. of course he knew that they had hurt others, but he didn’t know how the other victims were affected by that pain, or to what degree. but with kevin, steven knew his own pain, as well as connie’s. as stevonnie, they share the exact same feelings, and the exact same experiences. when kevin harassed them at the dance, steven experienced an anxiety attack for what might have been the first time. it stressed them out so badly that they unfused. so he knew how badly it had hurt connie, because he experienced that hurt with her.
steven wasn’t mad at kevin because kevin hurt him, but because he hurt him and connie. and steven felt how it hurt her. it was something new and foreign to him. that’s part of what makes fusion so intimate. you experience the exact same things as your partner, whether they be good or bad. and you understand each other better because of it. and steven understood the effect kevin’s harassment had on connie.