Once people got to know him it didn't take them long to realize he wasn't a heartless jerk despite looking like some kind of a bad boy. Kagami was quite a forgiving guy; why should he waste any energy hating other people? For him it was pretty pointless.
But the end of Winter Cup proved him how wrong he was, that there were some things he could never, ever forget.
When Kuroko waved at him to come closer to him and talk with Akashi, Kagami saw only his senpai and his Shadow's crying faces, tears in Riko's eyes when their opponents were trying to break his team and everything he could do was to hiss at players of Rakuzan, eyes blazing "I'll crush you the next time too".
Because there was no way Kagami could forgive anyone trying to make people hate the sport he loved.
He wasn't a saint.