K is the white-haired rock star, yes. His brother raped the soccer player somewhere in BRONZE. K, on the other hand, raped the then-girlfriend of the soccer player back in Zetsuai. I don't even remember if he had a reason for it, or if he was just mad at her for existing. (This is the character who cut off his own arm because he didn't want to do kendo anymore and he wanted his family to stop whining at him to take it up again.)

It's... not really fun to realize how screwed up that stuff I used to love as a teenager really was. I have very fond memories of Kizuna (Kai and Masa mmm), so I'm kind of afraid to revisit it and discover it was actually all sorts of terrifying or something.