Synopsis
Saeki Nozomi is a nurse stationed at the hospital where her cousin is being treated for an illness. Although she is currently married, her husband is away on a business trip, leaving her alone. As her period approaches, she feels a heightened sexual desire but strives to remain faithful to her husband, restricting her flirtatious behavior to her cousin, whom she regards as a younger brother. Meanwhile, Yumi, the cousin’s sister, works at the same hospital as a trainee while studying to become a nurse. She harbors deep feelings for her brother and worries about him constantly, though she carefully avoids crossing any inappropriate boundaries.