Reposting a very useful Voji comment
Page 1: Manbagi. (Obvious, not gonna explain her.)
Page 2: Tadano Hitohito [normal, average, common dude] and Osana Najimi [Osananajimi means childhood friend]
Page 3: Nakanaka, the chuunibyou girl. [Chuuni is someone with so-called "8th-grader-syndrome", where they pretend they're part of some fantasy schtick with lots of edge and stuff.]
Page 4: Onemine Nene, the "big sis" of the cast. Otori Kaede, good friends with Nene, the ditzy, slow and somewhat clumsy girl that gets lost all the time.
Page 5: Omojiri Miwa, the new teacher at the school who's unexpectedly slovenly at home and occasionally goes to sleep friday evening and wakes up sunday afternoon.
Page 6: Naruse Shisuto, the absolute narcissist. [He's a good guy at heart, though.]
Page 7: Katai Makoto, potential candidate for best girl. Everyone's scared of him as a delinquent, but he's really just a big softy who sucks at talking to others. Also page 7 is Satou Amami, who's bad at saying "No" to people and will do whatever someone asks of her. Yadano Makeru is the eternal last-place-character who loses every competition.
Page 8: Katou Mikuni, somewhat shy girl who was part of the 3-person-group with Komi during the Kyoto excursion arc. Wants to be a professional shogi player. Yamai Ren, the weird and creepy stalker girl who's unhealthily infatuated with Komi. Sasaki Ayami, the other girl from the 3-person-group with Komi during the Kyoto excursion arc; she's trying to keep her identity as an aspiring yoyo-professional secret from others. Komi Shouko, no clue who that character is, I think this person was introduced as a sneak peek in this chapter and will probably get a full introduction after summer break. Looking forward to finding out more about them.