Just to be clear: The guy didn't do anything other than to say "I don't like who you are." That only affected her because she wanted to be with him. She massively overreacted. (Though to be fair, he was the keystone of her social world, and so that would have cost her all the social connections around him.) Still, it's not physical or sexual assault.
Basically she just needs to say, "Oh, it's you. The Peten-chan hater. What are you doing here?"
But I kind of expect some scene where Kaori shows up, harem boy hits on Kaori, amusement ensues.
OTOH, JP loves to forgive their villains, so I wouldn't be surprised if it goes the route where harem-boy apologizes: "I'm sorry, I shouldn't have said these things." (While glossing over the fact that he made no attempt to contact/apologize earlier.)