For a Buddhist memorial service, the younger brother and his wife (Rio) returned to their childhood home where their mother with dementia and elder brother's family reside. The sister-in-law had left half a year prior due to exhaustion from caring for the mother, while the elder brother harbored unfulfilled desires. Meanwhile, although the younger couple had a good relationship, their sex life was bland, leading Rio to occasionally engage in self-soothing behaviors. Just then, the younger brother returned to Tokyo for work. Rio stayed behind to take care of her mother-in-law.
