The year is Showa 10 (1935).
Yohichiro returns to his parents' home in Yokosuka from England, where he had been studying, upon receiving news of his parents' unfortunate passing. He is greeted by a little girl with blue eyes who calls herself Mayu. Mayu is the only person left in the mansion to serve him as he takes over as the head of the Wakui family.

At first, Yohichiro distrusts Mayu, but as she takes care of him, he begins to open his heart to her. They are not related, not even family, but they develop a bond that is thicker than blood. The start of a modern love story between a beautiful maid and a world-weary young man.