As her exciting first year of high school begins, Sakurako Kawawa settles into her new lodgings. There, she meets her new roommate: the stunningly beautiful Kasumi Yamabuki! From day one, responsible and level-headed Sakurako and lazy, easygoing Kasumi find themselves at odds with one another... but with their matching mugs and one bed to share, Sakurako and Kasumi's friendship is just beginning!