Sea Tremors (RinHaru AU)

Young merman Haruka has lived in the wild side of the ocean for over half of his life. He didn't choose this, in fact, it was forced upon him after an unfortunate event at his former housing.
Thankfully, when he is nearly starved to death, a savior appears, going by the name Tachibana Makoto. But there's only so much a middle classman can do for the lowest of the social pyramid.
Soon, Haruka abandons this thread of hope and searches for another one. He searches aren't in vain and don't go for long, until he finds his fingers hopelessly intertwined in the stringed web of a shark-like royal, who will decide his fate.