About to start her first year of high school, Sakurako Kawawa settles into her new lodgings. But when she meets her new roommate -- the beautiful Kasumi Yamabuki -- everything changes! From day one the responsible, 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!