"It can't be! I've never been touched by a guy before...!" By chance, Mizuki gets a job as a babysitter-cum-housekeeper. But he's got to work for... a yakuza family! The gang is run by the late boss's four sons and is led by the eldest, Ryuichi. So, Mizuki starts babysitting during the day, and taking care of the brothers' sexual needs at night! They like to see him hot and bothered, and they use every trick in the book to get into his underpants. But one day Mizuki finds out their secret...!