Guess it's due to being middle schoolers but not liking someone and just rejecting them don't mean you have no emotions (unless he rejected her the most brutal way possible which I don't think at all because he was nice to her)
Sometimes I forget that the human MC is a middle schooler, so tis kind of bull was sure to come. But TBH I fail to see so far how this adds to the story ...
Are people seriously calling the first look into exactly why the MC stopped going to school and became obsessed with how to fall in love with someone (aka the literal driving force of the entire plot) unnecessary filler?
Even the past arc showed Yamori's obsession with love reaching the point that he'll willingly play matchmaker. Everything keeps tying into the central theme that he's trying to understand love, despite his warped lacking sense of it.