The Horniest Mermaid (Adult Fairytale First Time Anal Sex Erotica) - Furry-Tales, #11

Aria and her sea-people stayed separate from the realm of men, but when she catches a chance look at Prince Fabio celebrating his birthday on his galleon, she can't help but fall for him. A tempestuous storm sees the Prince cast overboard and Aria rescues him from a certain fate.  She uses her limited time on land to claim the real prize, taking the Prince as her first and doing everything she can with him in the time she has.