I lost my father when I was little, and I have lived alone with my mother for a long time. Although it was sometimes tough, I started to love my beautiful and kind mother as a woman. But when I got a job, my mother seems to be remarried to a man I met at work and trying to live a second life ... One day, I invited my mother to go on a hot spring trip with her parents as a celebration before marriage. To convey "future love" instead of "gratitude so far" ...