Nanji, Boshi No Gotoku

From Himnae Scans: A love story of 2 teenagers living in a small town near the Seto Island. Akimi, a high school student raised on the island, and Kai, who transferred there, troubled by his mother's affairs. Both harbor feelings of loneliness and emptiness in their hearts, and they are drawn to each other, experience misunderstandings, and gradually mature together. (might change)