Luna Varga(1991)

Luna Varga follows Princess Luna of Rimzbel as she discovers an ancient power to summon a dinosaur demon during a desperate defense of her castle. The catch: when the creature manifests, Luna becomes fused to its head and must serve as its mind, controlling its every move. When her younger sister is kidnapped, Luna embarks on a perilous journey to rescue her, relying on this strange bond with her monstrous companion. The series blends fantasy adventure with the absurd challenge of fighting enemies while literally attached to a demon's skull, forcing Luna to master both magic and monster combat to save her family.