This is the world of ordinary people - at least that's what alien civilizations think.
So I was chosen to be their experimental way of understanding humans.
The young man who was not willing to be a mermaid rushed into the darkness and saw the gods for the first time.
The god smiled helplessly, "Children, who is not an experimental subject anymore?"
Returning to the darkness, he knew, and had to know, that if he wanted to go home, if he wanted to be a true human being, he could only resist.
Fight with all your might!
It's quite novel and not overly clever.