Close friends through family ties, the Hojo and Asakura households share everything—town gossip, family matters, marital issues—nothing is off-limits. Life as a husband has been peaceful, and his sex life with his wife has been calm too, but lately he's begun feeling a lack of excitement. One day, without realizing it, he blurts out a question: which one is truly the bigger pervert, my wife or yours? Thus begins a test to find out.