You swim as fast as you can but the Merman is too fast for you, he eventually gets you in his arms, and then his penis emerges from the genital slit in his Merman tail, he puts it into your anus and he pumps sperm and semen into you, you feel pain, dizzy, and sick.
After what seems like hours, the Merman finishes pumping his seed into you. He lets you go and he disappears, you never see him again, it is as if he was never there, as you are contemplating what just happened, you feel pain in your private parts, your penis, urethra, and scrotum, wither and die and they become your clitoris, urethral meatus, and labia majora and minora, and vagina respectively, all of your new female private parts are separated from your anus by your perineal raph. suddenly feel pain in your legs, they feel like they are joining together, as if they are either being stitched together or conjoined. your legs join together into one and they get scaly, and the end of it becomes a tail fluke like that of a fish.
There is no doubt anymore, you are a Mermaid and you have a Mermaid's fish tail or a Fishy Mermaid Tail. You can never leave this virtual ocean world to the real world anymore, nor can you turn back into a human male again, you are stuck as a Mermaid Girl in this Ocean Virtual World For all of Eternity and even beyond that.
GAME OVER