Dunno how I feel about that. Imo, there were nothing strong between them in term of relationship grow. They just fucked and that's all. And never author showed if his feeling was beyond being just CF. And even, in chap 62, he admited that he fall easily after having sex and he think is a bit of shallow.
He never tell her he was in remedial classes to begin (it's only because Akito ask him if they can meet back in chap 58 that she learn about that)and he never contact her. Sooo yeah seeing him with the pres, she can only react like that (I can imagine that she feel dejected because he's out with the pres for the festival, so like she feel he have made his choice. Remember back in 58 she wanted to met him). so yeah, he lose Akito as cf for now (real lose as she shunned him)