Building Castles in the Sand (слэш)

Yuuji never believed in sea monsters—until he was nearly eaten by one.
To be fair, Satoru didn’t mean to scare him. He just wanted to help. With his teeth, and maybe a little kidnapping.
Shipwrecked after a leviathan destroys his vessel, Yuuji wakes up on an uncharted island—and straight into the obsessive care of a powerful, lightning-touched creature who doesn’t quite understand humans but is very eager to learn. Armed with no concept of personal space and far too much interest in Yuuji’s body, Satoru claims him as his mate.
Now stranded on an island with nowhere to run and no dignity left to cling to, Yuuji declares one thing: If this beast wants him, he’s going to have to earn it. And thus begins an unraveling courtship—clumsy, obsessive, and unshakably devoted.