Hentai based on the popular manga "ZERO SUM GAME -SEX CRIME-" by Kudara Naizou, which was published from 1999 to 2002.

Yuka and Yuzaki have been living in a happy marriage for many years. Yuka has long been a fan of the popular pop-idol group "Zero Sum Game", and her husband is well acquainted and is the senpai of the lead singer Keichi-kun. So it happens that Yuzaki gets his beloved a cherished ticket to one of the "Zero Sum Game" concerts. After the concert, he hurried to the dressing room to his kouhai to introduce him to his wife Yuka. Keichi immediately realizes that Yuka is a hot sexy thing and he just has to fuck her. At a joint party to celebrate the acquaintance, Yuzaki drank too much and passed out, and Yuka fell into the hands of a depraved band of musicians...