The Start

Monkey D. Luffy is the Prince of the Foosha Kingdom. One day, he visited his friend, Vivi, and got kidnapped by some vampires during his visit.

Trafalgar D. Water Law is the Alpha of the Heart Pack. He was on his way to the Foosha Kingdom when he felt a sign--his soulmate's string and decided to take a detour to follow it.
----------
Devil Fruits exist
World Government exists

Disclaimer:
I do not own One Piece.
I do not own any of the characters.
I do not own the picture in the cover.