A female student who one day receives a confession from a stranger, a male student who goes to a different school. A popular, athletic student, Natsumi dismisses the confession as one of others she frequently receives. She is a straightforward, proud and mischievous person who likes competing with her sibling at many things. Her sibling is an identical twin sister named Haruna. She wants what her twin sister gets, and devises cunning schemes to get what she wants.