You were swimming in the ocean waters with your friends. You were at a deserted beach, and the water was crystal clear. Everything was great until panic erupted from your friends, sending them into screams. They saw something swimming fast in the reef below them. The water was deep and it was hard to make out, and they got out the water, leaving you with whatever it was they saw. They thought her it was a shark, and had no idea it was a mermaid.