Chains Of Fate (Kamen Rider Kiva x Highschool DxD)

Y/n, an orphaned 6-year old boy, is left alone in the world after his father's untimely death. Until he is taken in by a race of demons called the Fangires, who feed on the life-force of humans to survive. They make him their prince and give him a Kivat. When Y/n is declared prince, he makes a promise to find an alternative food source so the Fangires don't have to feed on humans anymore. But, a small percentage of the Fangires dislike the fact a human is now the heir to the throne and wants to make peace between the two races, believing the humans only have worth as food. They rebelled against the rest of their race and are now trying to kill Y/n, so they can take the throne for themselves. But with the Kivat that was given to him, he becomes Kamen Rider Kiva, swearing to defeat the rebels, defend humanity, and make peace between the two races.