A 'Princess' for a Sea Prince
Harry Potter x One Piece
Fem!Harry x Fukaboshi
Mermaid!Harry
Seer!Harry
MoD!Harry(?)
-She calls Jinbei, Jin-ji
-Shyarly sees her coming, and that she has a similar power and takes her under her 'wing'
-She also informs the king that she will need training that much depends on this (how she meets Jinbei and Fukaboshi, fishman and merman karate respectively)
Right before Harry comes into her magical inheritance, Gringotts sends her a letter and portkey. Magical inheritance happens when witches and wizards come of age at 17, though sometimes for witches it doesn't occur till they are 18.
Harry is one of those cases, so the second blood war has just ended a few months previous. And in that time Harry has done everything in her power to make things up to the goblins (and has unknowingly succeeded), catch the remaining free death-eaters, and rebuild the magical landmarks (mainly Hogwarts).
She has been living in Grimmauld Place, where she recast the fidelious charm so no one could get in. Not even Ron and Hermione, who have been acting weird recently.
It is right before she receives the bank letter, that it all goes to hell in a hand-basket for her.
The tabloids have caught wind that she still hasn't come into her inheritance, which means she is to gain more power, they also start to question how she offed Voldemort, at only 17 when Dumbledore couldn't. They call her the next Dark Lord(Lady), the next evil.
This goes on for the next couple days/weeks, where in that time the Weasleys 'disown' her and Hermione turns her back. Neville and Luna are still with her and supply her with things, since it is no longer safe to leave the house. That's when the letter comes, her salvation.