Yayoi Yanagida and her husband got married after a workplace romance and officially registered their marriage. Yayoi heads to her husband's family home, where she is shocked and bewildered to see her mother-in-law wearing only a fundoshi loincloth. In this region, it's an old tradition for villagers to wear fundoshi as lower garments, a custom that makes Yayoi feel uneasy. When she refuses to wear one herself, her father-in-law becomes furious. Pressured by her husband and mother-in-law, Yayoi reluctantly agrees to wear the fundoshi. However, during a gathering introduced as a "coming-out party," Yayoi finds herself exposed to the lewd stares of the villagers.