So a big deal is made of what Moritani did to Manabe, and with good reason. Kotoura forgives her because she reads her mind and sees she is genuinely sorry. Fair enough. But later in the series she's seen hitting Manabe for varying reasons, and very little is made of that. I know he isn't being exactly nice to her, but after what she did (especially in the manga version, where she accused him of raping her instead of stalking, and he was stabbed rather than just beaten up) he has good reason to dislike her. It seems weird that she's never called out for assaulting the boy that she more or less put in the hospital.
I can think of two reasons, although I believe more in (1) as the others (especially Manabe) were extremely reluctant to let Hiyori in: 1. Yuriko has to maintain the Club Stub. Given their history of getting members (see episode 2), they'd need a large safety margin than just Haruka and Manabe. 2. Even they don't believe in Hiyori, they believe in Haruka, right?