Height: 170 cm

Birthday: July 22

Sign: Cancer

Age: 27 (At the beginning of the series)

Sumire's has her strong points, she has graduated from not only Tokyo University but also Harvard, she has a successful career as a reporter, and her co-workers think of her as a cool and collected person. Things start to fall apart for her though, at a drunken holiday party she punches her lewd boss out, getting demoted to life style affairs at the paper. Then her fiancé leaves her for his old girlfriend because Sumire is to intimidating for him.

Her life starts to pick up again when she find a young man in box outside of her apartment and decides to take him in for the night. But he doesn't want to leave, so they come to the agreement he can stay if he is willing to be her pet!