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Kotarou Hasumi (蓮見小太郎 Hasumi Kotarou) is a secondary character who belongs to the Manga Research Society. He is Makoto's younger brother.
Kotarou is a long blue-haired boy whose face is covered by his bangs. He wears two hair clips on his left side, star earrings, a dark shirt underneath the school winter blazer, a blue-striped tie, and pants. To match his sister's attire, he wears a blue jacket, sunglasses, and a satchel.
Kotarou is a boy who holds the eighth position in the Rookie Top 10.
He really admires Shigure to the point of calling him as Shigure-sama. He also clearly dislikes Eruna because of her relation with him and agrees with his sister's claims that the Manga Research Society members have a deeper relationship with him than Eruna. He is usually backing up what his sister says with short words, although it is unknown how he actually talks if his sister is not present.
Kotaro was introduced in a newspaper article as the one who held the eighth position on the Rookie Top 10. Eruna recognized him as one of the students who emitted a scary aura when she was being invited by Shigure to join the Manga Research Society some time ago.
Seeing a Sixeen-day-old Moon
In Treasure Hunt Event, Kotaro followed his sister, Makoto, to confront Eruna. All he did was nod in agreement at his sister's words. He also joked about Otone's condition, who previously commented at Makoto's words provocatively, as a club-less person verbally, which angered Eruna in return. When Eruna was about to catch him, she fell into a slope. When Otone herself went to save her, both of them ended up falling there. The twins, who initially did not want to pick a fight with them, quickly went and informed their condition to the first-aid committee.
Being identical twins, they are almost always seen together anytime and anywhere. Makoto is the one who usually speaks while Kotaro just backs her up.
Kotaro admires him a lot to the point that he calls him as Shigure-sama.
Kotaro dislikes Eruna and sees her as hostile due to her relation with Shigure.
His surname, along with his sister's, comes from Hachisu Shrine (蓮神社), located on Toyoshirocho, Isesaki City, Gunma Prefecture.