After the death of her parents Tsubaki, having few other prospects, accepts a job as a waitress at a rural onsen (hot spring resort) where her family stayed when she was a child.
She is reunited with Yuuki, the son of the onsen's owners, who often teased her when they were children. Yuuki has now grown up into a handsome young man, but she is shocked to learn that her parents had promised her in marriage to Yuuki when she was a child, and Yuuki intends to hold her to that promise!