i have an idea for a roleplay about a guy who finds out his grandmother/mother is a mermaid and that he carries a very important bloodline, but i am not sure if i should go through with it or not. 

basically, he finds out the truth about his mothers side of his family, which was a total mystery that she had refused to talk about while alive. 
This is after he meets a merperson whom he saves when he finds them washed up on shore, a member of a royal bloodline. 
Then, more occurs that would change his life forever.