Tomoyuki left his parents' home and lived alone in a dormitory at school. Three years passed in the blink of an eye, and finally his graduation ceremony came. As he was walking his last memorable route to school with his friends, a woman suddenly appeared. Her beautiful smile was overflowing with kindness... It was his stepmother, Rinko, who had come secretly to celebrate Tomoyuki's graduation. Tomoyuki took Rinko, who had drunk too much because "today is a celebration," to her accommodation, and there, guided by his beloved stepmother, he took another step towards adulthood...