Nagomi feels uneasy toward her new stepfather. For the sake of stability, she suppresses her complicated emotions and resolves to support her mother's remarriage—yet the reason behind this decision turns out to be unexpected. The truth is, her new stepdad agreed to marry her mother because he was attracted to Nagomi's slender, petite body. Once again, he attempts "sex education" with the shy girl, leaving her flustered and confused. But in reality, her mother was fully aware of his true intentions all along…