Peppy and outgoing, Mikazuki Kiryu is a second-year middle school student and younger sister of Yuzuki Kiryu. She enters third-year middle school when Keita starts his first year in high school. In spite of her age, she is far more mature of the two, and tends to keep the most level head when her sister is losing hers. An underclassman to the rest of the cast, Mikazuki looks up to everyone, especially Keita, who she fashionably has a crush on. However, she seems to be just as interested in amusing herself by watching the antics and reactions of others than actually winning him over.