You were scared of the sea since you were a child, you had no clue on how to swim either so you keep your distance from the sea.

And now you had grown up and changed but the fear of the sea still stayed with you, and everyone around you made fun of you for it.

Your 'friends' though it was funny to throw you in the sea for fun but you ended up drowning and was rescued by two mermen and they placed you in a cave.