Umi Asagi, a university student, is the recipient of presents and confessions from a mysterious individual named Kamibukuro-kun. He always keeps his face concealed with a paper bag and is incredibly shy but relentless in pursuing Umi, whom he loves deeply. However, Umi's best friend considers Kamibukuro-kun as an annoyance and his love for Umi as obsessive stalking. In a fit of anger, Umi's friend frightens Kamibukuro-kun, commanding him to never come near Umi again.
Following Umi's friend's warning, Kamibukuro-kun disappears. But to Umi's surprise, she never saw him as a troublemaker, and she enjoys his presence greatly. When Umi finds herself in trouble, will Kamibukuro-kun emerge from his hiding place to rescue her?
