My brother's couple and my mother... and somehow me came to a hot spring trip in the suburbs. Because my sister-in-law, Nao, prepared tickets for two pairs, I was forced to participate to make the numbers. The inn was more luxurious than expected, and my excited mother and brother quickly got drunk and passed out after drinking alcohol. While the family was sleeping, I was left alone with my beautiful and kind sister-in-law... Her fair skin, flushed red from the bath, peeks out from her yukata, and I can't take my eyes off her. Perhaps she noticed my gaze, Nao came closer to me...
