START-611 Swapping Village: The village I married into was a perverted settlement where NTR (Netorare), where wives are swapped, is a form of entertainment. - Haru Shibasaki

A few months after her marriage, Haru Shibasaki moves to her husband's hometown, a remote village, due to her grandmother-in-law's ill health. While bewildered by the village's unique rules, Haru tries to adapt to the village life. However, on the night of the housewarming party, she is attacked by her husband's senior couple. This incident leads Haru to discover a terrifying "sexual custom" that has been passed down through generations in the village.