Kotarou Higuchi is a sixth-grade student who must work hard to gain admission to a good middle school, while also managing the responsibilities of living alone in an apartment. One day, as he leaves for school, he is surprised to find an unfamiliar older girl in a frilly black dress waiting at his front door, asking to be his friend. Despite his attempts to ignore her, the strange girl persistently follows Kotarou all the way to school and back. Relenting, Kotarou learns that the girl's name is Misha and that she is his new neighbor, supposedly from Heaven to work on becoming a full-time angel. What will become of Kotarou and his life with this "clingy angel"?