Skyblue Shore(2006)

Sorairo Kaigan

Tomo, a sweet high school girl, loves living near the beach. However, after her parents got divorced, her frequent beach visits became no more. Until one day, after getting harassed on her way to school, Tomo is rescued by a selfless, very attractive stranger who somehow reminds her of the ocean. As the stranger leaves, he drops his keys, and Tomo realizes the keyring has the same stone as one given to her by a long lost friend from her childhood. Could he be the same person? Tomo believes the sea can bestow treasures on people, and she may be about to be proven right in ways she didn't imagine!

(Source: Tokyopop)