■The protagonist has a big penis and a strong libido. He has no sex life with his wife, who is much older than him. Once again, the good-for-nothing old man is tormented by guilt but he gives in to the temptations of Lala's sexy body and they end up having a physical relationship again.
■Lala (sister-in-law) is much younger than her sister (the protagonist's wife). She seduces the protagonist with her sexy body. She was originally quite slender, but something happened three years ago, which caused her breasts and butt to get bigger.
■Wife (Yumi) She married the protagonist through an arranged marriage several years ago but she never had a strong libido and could not withstand the protagonist's big penis and libido, so they soon became sexless.