Yuki, a newly married married woman, has a secret that she cannot tell anyone. It was an affair with her childhood friend. The two loved each other before they got married. ``He and I are brother and sister in our hearts,'' says Yuki. But it's a ``convenient sex friend'' who calls her to a hotel and fucks her as much as she wants. The two of them have been together for a long time, so they know everything about how to feel good. Never do this to a husband or wife