This Boy Caught a Merman
When a picture of his late grandfather falls into the ocean, Shima jumps in after it without thinking. Nearly drowning, he is saved by a very perfect stranger - the young merman Isaki. Shima and Isaki quickly bond in ways neither anticipated. After all, Shima and Isaki aren't just from opposite sides of the tracks but from entirely divergent species, which makes maintaining a long term relationship anything but easy sailing.