A boy is sitting at the beach and out of nowhere a water deity pops out of the water and gives him a kiss. Immediately she turns into a normal human. The boy fell in love at first sight and promised to love the girl forever. But she can only be a human until she turns 16 and after that she must return to the waters and live forever in the deepest abyss of the ocean where no light can penetrate the darkness. The End
Oh and she turns pregnant 2 days before she has to go back. That's why they're crying cause their baby is going to die (since well mermaids lack the most obvious parts of a woman's body). The The End
By the way, this is a joke post, I'm deleting this once everyone has had their laugh.