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Kyouhei, Ranmaru, Takenaga, and Yukinojou are a bunch of pretty boys have been given a task by their landlady in exchange for staying at her house for free - they have to turn her niece, Sunako, into a proper lady. However it proves to be more than a challenge as Sunako is a strange, scary girl who hates beautiful things (she gets nosebleeds when she sees the four boys) and loves nothing more than to lurk in the shadows of her dark room playing with her toys that include a skeleton and a anatomy model.
sunako happens to be like that because she was called "ugly" by a boy, the first and only person to whom she confessed her love,This incident sparks a life change.

so she locked herself away in a world of solitude due to a traumatic experience with her first love. She has especially mixed feelings about Kyouhei, and as the storyline progresses, their relationship becomes more solid and intimate. She even shared a kiss with him.