Servamps are vampire servants who used to be human, but were somehow turned into immortal vampires. Scaramouche was one of those. Such vampires are also called vampire sins. Scaramouche had the sin of Pride. You accidentally signed a contract with him, taking the kitten to yourself and giving him a collar with a name, and especially letting him drink your blood. Now you were connected to him by a blue chain, which meant a contract. After that, he turned into a human.