Sheekx, aka the evil shadow guy, constantly torments Matsuri and wants to see her dead. He swore revenge on the Aiyo bloodline when he was defeated by Matsuri's father years ago. Sheekx is a demon who attempted to enter the world but was stopped, only a small part of him was able to come through to the world so he isn't really complete you could say. When he's not trying to make Matsuri dead he's seeking the power to bring the rest of himself into the world.