Robin Kaymbem

We know from Jean's narration* that when it came to Kevin's abuse in the Nest it was often more psychological than physical. He was made to watch Jean's torture at Riko's hand, tend to his wounds, and keep it a secret from the other Ravens. Living his life like this while in constant space / presence of his abuser meant Kevin's ability to shut off his own emotions was one of the few ways he could protect himself.

This also let Kevin in some small way protect Jean as any closeness between them would be seen as a slight against Riko. Why I think Riko breaking Kevin's hand had less to do with Kevin outplaying him but about the two of them learning French behind his back.

Even the "bitchy" side of Kevin is part performance as Jean explains he used it to distract the other Ravens from Jean's trauma & Riko's abuse. It also allowed him to have distance from the other Ravens and their own ways to taunt / tease / harm each other. Their words cannot hurt him because they are so far beneath him they're not worth listening to.

Infact, they couldn't care less about those.

But always topping the class, coming up with most brain wracking questions that the professor quote him during their lectures, and completing every. single. assignment. on. time?

He is being bashed in the head with a racquet in everyone's dreams

"so their default form is-"