Shintaro, an ordinary office worker, lived happily with his beautiful wife Saki. One day, when he returned home from work, he found his brother trying to force himself on Saki. Shintaro was overcome with indescribable emotions as he watched his poor brother and his wife accept it. He wanted to let his wife sleep with other men more and more... Shintaro's "cuckolding desires" were realized one after another.