When Iroha got married ten years ago, she became a wife to her husband and at the same time became a mother to a son who was in junior high school. Her husband had a son with her ex-wife and she was worried about whether they would get along, but she got along fine. However, she had not had sex with her husband for many years and was frustrated. One day, her husband bought her a balance ball. When I invited my girlfriend's son to exercise with me on a balance ball, he got excited.