The Kuramoto family is a three-generation family of Eri, a son and a couple, and grandson Kameji. Kameji was raised by his grandmother's collar from an early age on behalf of his son and his wife, who are busy working together. One day, we all decided to go on a hot spring trip to celebrate Eri's 60th birthday, but as the boy and his wife were still busy along the way, the clouds went suspicious, and Eri and her grandson decided to head to the inn. The two who arrived at the hot spring ...