Aoi Kirishima 桐島葵

She is Haruto's elder sister. She came back home from college in Tokyo to student teach in order to get her teaching license. Out of the two siblings she acts the least mature. In Tokyo, she lives in Ayano Fujikawa's dormitory and is next door to Yamato Akitsuki. She is the one who shows Haruto a picture of when he first met Eba when they were children. She thinks that Haruto and Yuzuki make a better couple than with him and Nanami. She is a heavy smoker, extremely lazy, and leaves her room trashed, which usually results in Haruto doing most of her chores. Haruto lived in the dormitory with Aoi, until he got his own apartment.