The story centers on a girl who is told she only has six months to live. In the spring of her first year of high school, she confessed to a boy who is in the same class, even though it's their first time meeting. The two gradually grow closer as lovers, and on her birthday, they go to see the 'Strawberry Moon', which is said to be a time when you will be forever bound to the person you love if you watch it together.
