Because her only daughter is too busy with work to do housework, her mother Ikumi has decided to live with her for a while. She will do anything to help her see her first grandchild. But as she lives with her daughter, she discovers that her daughter and son-in-law don't have a sexual relationship. One night, in the couple's bedroom, Ikumi witnesses her stepson's erect penis, which has been rejected by her daughter and has nowhere to go. "It's a shame that his penis has no outlet..." From the moment she saw the penis, Ikumi's attitude towards her stepson changed...