A large mansion in a certain countryside. During Obon, all relatives return to their hometowns all at once, and it becomes very lively. Strangely enough, this summer is the year when the "Finding a Family's Son-in-Law" will be held. This time, the amateur men recruited by ZUKOBAKO will be involved in this unique relative's "summer vacation". You have to enter the hot spring together, have a sketch in your free study, have your cock thoroughly evaluated, and have a big orgy to satisfy your family's sexual desire. A miraculous summer vacation begins.
