Luceria

The Servant summoned by Kaito Takagi using a card is a viscount-class demon with a selfish and foul-mouthed personality, who has a fondness for magic cores. This demon specializes in magic that melts enemies and often loses control during battles with monsters, displaying excessive power. Her selfish nature often troubles Kaito, but the kindness she occasionally shows soothes his heart. Although she feels jealousy toward Sylphy, she nevertheless maintains a good relationship with her. Furthermore, by leveling up her skills, she is able to transform into a beautiful adult woman.