Ryushi arrives at his new apartment complex, where the landlady is his second cousin, Kozue, who is also in high school; he quickly develops a crush on her, but when she trips and falls on him one day, she suddenly becomes a totally different person.

Not only is Kozue suddenly acting like a delinquent, she doesn't even know who Ryushi is; his neighbors, Megumi and Tamami, rescue Ryushi from a beating; he learns that when Kozue gets a shock, she's taken over by a different personality, Saki.

After Kozue faints from embarrassment due to the wind blowing up her skirt, she wakes up with a shy and childish personality of Nanako; the other residents make Ryushi babysit Nanako, and she proves to be quite a handful.

Ryushi goes to art college for the first time and meets his elegant but terrifying teacher, Miyabi; on the way home, he runs into Kozue and Tamami; they go to the park and encounter a maid, then help her search for her missing stamp card.

Ryushi follows a trail of petals to find the perpetually depressed Sayoko, who earns a living by assembling artificial flowers and doing other odd jobs; he ends up helping her and her cheerful daughter Asami make flowers while learning how they live.

Tamami barges into Ryushi's room and, using a compromising photo, blackmails him into helping her; she makes him come to her high school and carry her bonsai tree home while revealing the limitless depths of her mischief.