Love, Come In, The Water Is Fine

Muichiro lures sailors into the rocks every day of his life. Genya is one of these Sailors.
When they meet, they can tell they aren't like the stories.

And so ensues the chaos as half the pirate crew and half the sirens manage to fall for each other, and try to keep it a secret

or
Kny Sirens and Pirates Au

Ships: Genmui, Sanegiyuu, Inotan, Zennezu, Obashinomitsu
Cover Art creds: Bisexualdragon on Deviant art