A successful department manager is happily married to Rei, a beautiful former receptionist. Hoping to share some of that happiness with his awkward, older virgin junior Saji, he invites him home for dinner. While drunk, he proposes letting Saji enjoy a mock-marriage experience with Rei and leaves them alone. After three hours of relentless sex and 17 creampies without pulling out, the atmosphere between all three changes—and the husband realizes he may have handed his wife to another man.