The Vampire Rosario the real boy who lived

Matsu is surprised when at the age of 5 he is told that his parents Issa Shuzen & Akasha Bloodriver aren't his biological parents, they adopted him. His biological parents are James & Lily Potter, proud parents of the Boy-Who-Lived, Matsu had originally been named Harrison Potter, twin brother to the Boy-Who-Lived. Matsu seeks vengeance against those who abandoned him at the Dursley's and to what would likely have been a life of abuse. Matsu has been preparing for his vengeance against those who wronged him, and with the Triwizard tournament - including Yokai Academy this time around, so Quadwizard tournament? - being hosted at Hogwart what better time to seek vengeance than now? All those that have wronged Matsu have no idea what's about to hit them. (Yaoi Harem and no Moka Akashiya) Vampire! Harry