Miyako Kaneshiro lives alone in a house that looks like a hot spring inn. Her son and his wife and her grandson came back using her consecutive holidays, but Miyako stubbornly refused to take a bath together. She has a tattoo on Miyako's chest and wanted to keep it a secret from her family. However, she is found by her grandson Yuto, and instead of rejecting her tattoo, Yuto becomes sexually aroused, and she has a physical relationship with Miyako. Miyako was captivated overnight by the sexual desire of a young man.
