Rin lost her husband two years ago and had been living with her stepdaughter. Later, her stepdaughter got married, and the couple moved in, forming a household of three. Though her loneliness had faded, she still longed for physical intimacy. One day, Rin witnessed her daughter and son-in-law having an affectionate conversation in the living room. Watching them, she began masturbating, but found her fingers too thin to satisfy her—she craved something more. On another occasion, she was having a drink with her son-in-law when he accidentally spilled alcohol onto his crotch. As he hurriedly tried to take off his pants, Rin caught sight of his erect penis. Her heart raced, and in that moment, a new desire awakened within her.