Her father is away on a company trip, and she has had a lot of sex with her stepmother, whom she has always admired, and is living a creampie life.

Even now, six months after he remarried, Mai still couldn't get along with his step-son. At that moment, my husband's company trip was decided. It's the first night I spend with my first breath and my life alone. Despite her guilt as a second wife, Mai tries hard to communicate despite her anxiety. However, his brave figure unconsciously stirs up his innocent breath... and finally the two of them cross the line of parent and child.