a royal merperson, a bit of a dipshit, too selfish and too unreliable, and in his father's eyes a disapointment in general.

he's being sent away from the kingdom (so he would get an opportunity to get away from everything, realize what really is important and better himself? or was the intention for him to never come back?). he meets a person, learns new things, realizes there's more to this world than he thought,, anyway this is not very original, you've all heard this story before.