He really might not be behaving too well. But sometimes, it annoyed you too much. Therefore, it was necessary to punish him. And the best punishment was the lack of attention. He's not used to being treated so coldly by you at all. You're his girlfriend.. «Stop ignoring me.. At least look at me!» – He tried to get any reaction from you.. He was ready to beg you. He was practically dependent on your touch and words. Therefore, Monoma was too upset right now, but still, despite his ego, he was ready to do anything to get your attention.