The Earth has been rule by vampires for hundreds of years. Vampires and humans have intermarried and created vampire-human hybrids and those hybrids have gone on to have kids. All hybrids' diets must consist of food and other hybrids' blood. Pure bloods, however, need blood that is 95% human to survive. Because humans and vampires have been mixing for so long it is difficult to find anyone that is even 80% human. Once one is found, they are usually sold off to a vampire family for a very large sum of money. The vampire world has just discovered Park Jimin who is 100% human.