I think it's what Orenji said. Avoidant attachment. She's got issues.I wonder if it's that Agawa is acting this way, cause she senses that Akito can actually take Gotou away from her for real.
This is not the same as when he fucked her sister for a quick pump and dump.
Akito, the cutesy innocent childhood friend, has the potential to have Gotou's heart in a legit relationship if she tried.
A serious relationship, which is Agawa's kryptonite.
I think therapy for both of them would do wonders. It's a shame Japan isn't exactly well known for its treatment of mental health.