Sayaka Sumino (隅野 さやか)
Sumino Sayaka is one of the main characters.
Sayaka is a beautiful young girl with brown colored eyes, blonde hair and pale skin. She has a flat chest, even by Japanese standards.
Sayaka is level-headed and assumes the straight-man role, often moderating interactions between Yoshiko and others. She is kind and worries about being boring. She is very sensitive, especially when others point out her small chest, which appears slightly small, even after she pads it. She sometimes loses her patience. Most people acknowledge her kind aura and the binding and relaxing effect it has on everyone.
She tried her best to befriended Akuru. While she considered him scary, she changed her view after Yoshiko told her that Akuru had no other friends and she took pity on him and said that she will become his friend and told him to smile. Like Yoshiko, she calls him A-Kun and though she felt sorry for him she seems to genuinely see him as friend and often worries for him when he gets angry.
Akuru is shown to consider her as such as well since he views her as "normal." Akuru even went on a vacation with her and the others after she pointed out he was somewhat weird and draws such people near him.
Yoshiko is a close friend of Sayaka, despite getting dragged into almost all of her shenanigans.
Ever since Sayaka encouraged her, Ruri likes Sayaka and seems to prefer her over Yoshiko. Ruri sees Sayaka as surrogate big sister since she has common sense and is always kind to her when trying to help.