Ichika, who loves caring and wants to do work that pleases others, is sent to the Ashida family for two days as a part-time worker at a housekeeping service. The client, Ashida couple, are left their house and are not there. The Ashida brothers, who are in the midst of being a shut-in and in the midst of puberty, take advantage of their son's position and play with Ichika's body like a game... "At first I thought it was a trivial prank, but..." Ichika falls into a hell of orgasm, pursuing a series of lewd acts called pranks, which are escalating as pranks...