Shirakawa Yuu will be living together at the mansion of his stepfather, who is the remarried partner of his mother after more than a decade. There, he will find himself with his stepsisters, Kyoko, Suzuko, and Anko. Yuu, who is an archaeologist and often away on long-term assignments, will use his stepfather's study as his actual room, where he discovers a suspicious bottle. It turns out to be a "cursed bottle" that requires the collection of women's love juices within a certain period, or else the greatest disaster will befall them!! Thus begins the thrilling everyday life under one roof with the three naughty sisters who care deeply for their brother...
