Марута Кайо

Kayo Maruta is a supporting character and ex-vice-president of the student council. She is best friends with Mitsuko, who she affectionately calls Micchan. Kayo is one of the few people who dares to talk to Mitsuko casually and lives to see another day; she also is seen at Micchan's side for much of the latter half of the manga. Glasses-senpai talks formally with everybody else. While on the student council at Aihara Academy, Maruta was dedicated and very diligent at making sure people are rule-followers, even chastising Yuzu while it's her first day there.

Eventually, the brunette lightens up later on and shows her softer side for Micchan and the readers, as well as the group that went on the summer trip in volume 8. During the extra in volume four of the manga, she reveals her surname and her past position in the council.