A spiral love story.

Kouno Jun is a lively character who lives life with all his might. In kindergarten, he falls in love with Hasebe Rino, the most beautiful girl in his class, and he confesses to her. Hasebe accepts his love, but the moment she gives her answer, she vanishes on the spot. Failing to figure out what's going on, Kouno asks his friends about Hasebe, only to find out that no one remembers a single thing about her. She has just vanished, along with all memories about her, except for those of Kouno.

While Kouno leads a weary and desperate high-school life, Hasebe appears again as a transfer student. However, this Hasebe is not exactly the Hasebe he knows...