Mermaids sometimes come to the surface, pretend to be human. See what that's like. She walks upright, but balanced on knives, and that's a pain you'll never see. All she wants to do is find the nearest bridge and jump off it, down into the depths below; all she wants to do is taste life, up here, for a second. Womanhood is just a mask she wears, it's the cage she lives in, but the sea and the smell and the water are calling to her, all the time, louder than you think. When she sings, she isn't singing to you. She's singing for herself.
She comes to the surface and you think she's there for you: Saw you passing by, stopped combing her hair with table utensils long enough to sing a song, scrambled up onto the rocks. This is the lie men tell themselves about all women, but most of all about the mermaid. That Clark Kent is the truth and before you, mermaid was the best she could do on her own. But she's not here for you. Clark Kent is a lie, a cover business: You're here for her. Forget it and drown.
Even if you survive, even if you live to be a hundred on the hard dry surface, you'll still never forget the song you heard her singing.