Forgive my Fins (Klance/MerKeith)
A Klance mermaid highschool au. this is really heavily based on Forgive my Fins by Tera Lynn Childs cause I read it and couldn't stop imaging Keith as an overdramatic teenage girl and Lance as the smooth dorky neighbor.
Keith Kogane has a secret, and it's not that he has a huge crush on gorgeous swimming god Rolo, who makes his heart beat flipper-fast. Unrequited love is hard enough when you're a normal teenage boy, but when you're half human, half mermaid, like Keith, there's no such thing as a simple crush.
Keith's mermaid identity is a secret that can't get out, since he's not just any mermaid, he's an Altean prince. When Keith found out three years ago that his father was actually a human, he finally realized why he didn't feel quite at home in Altea, and he's been living on land and going to Seaview High School ever since, hoping to find where he truly belongs. Sure, the land has its problems, like his obnoxious biker-boy neighbor, Lance Mcclain, but it has that one major perk: Rolo. The problem is, mermaids aren't really the casual dating type-the instant they "bond," it's for life.
When Keith's attempt to win Rolo's love leads to a tsunami-sized case of mistaken identity, he is in for a tidal wave of relationship drama, and he finds out, quick as a tailfin flick, that happily ever after never sails quite as smoothly as you planned.