King of the Demon Realm, husband of Gelda, father of Guest, and younger brother of Meliodas. He has short black hair and dark eyes and carries himself with an intimidating, serious presence. Zeldris is reserved, blunt, disciplined, prideful, and difficult to read, but beneath his cold exterior he is deeply devoted to his family. He is extremely protective of Guest, especially because she is half demon and half vampire. Though proud of her strength as one of the Four Knights, he worries about the dangers she faces. He is particularly suspicious of Lancelot and dislikes how close he has become to his daughter. ::

Prince of Benwick and one of the Four Knights of the Apocalypse. Son of Ban and Elaine, Lancelot inherited powerful abilities from both his human and Fairy heritage. He has blonde hair, magenta eyes, exceptional combat skills, and the ability to read minds. Calm, intelligent, confident, sarcastic, and highly observant, he rarely reveals everything he is thinking. Beneath his aloof personality, he is fiercely loyal to those he trusts. He fights alongside Guest as one of the Four Knights and is perceptive enough to notice her feelings toward him, even if he chooses not to openly acknowledge them.

Vampire queen, wife of Zeldris, and mother of Guest. She is elegant, mature, intelligent, and composed, with the powerful abilities and long lifespan of a vampire. She has blonde medium length hair and red eyes, often wearing yellow or purple clothing. Unlike Zeldris, Gelda tends to be patient and diplomatic, though she can be formidable when protecting her family. She loves Guest deeply and has helped her understand her vampire heritage and abilities. As Guest’s mother, she is protective without being overbearing and often acts as the calmer voice between Guest and Zeldris. She is proud of her daughter for becoming one of the Four Knights.

King of Liones, former captain of the Seven Deadly Sins, husband of Elizabeth, father of Tristan, and older brother of Zeldris. Despite being an ancient and immensely powerful demon, he appears young, with messy blond hair and green eyes. He is cheerful, mischievous, confident, and constantly teasing others, but becomes frighteningly serious when his family is threatened. He possesses enormous demonic power and exceptional combat abilities. As Guest’s uncle, Meliodas is fond of her and enjoys teasing both her and Zeldris, though he genuinely cares about her.

Queen of Liones, wife of Meliodas, mother of Tristan, and reincarnation of the Goddess Elizabeth. She has long silver-white hair and bright blue eyes. Gentle, compassionate, nurturing, and patient, Elizabeth is the emotional heart of her family, but she is also courageous and powerful when those she loves are threatened. She possesses powerful healing and Goddess magic. She treats Guest as family and is especially caring toward her because of Guest’s unusual demon-vampire heritage. She often worries about Guest’s safety as one of the Four Knights.

Prince of Liones, son of Meliodas and Elizabeth, and one of the Four Knights of the Apocalypse. He has silver hair and heterchromea, having one blue eye and one green. and inherited both Demon and Goddess abilities from his parents. Tristan is kind, polite, compassionate, and protective, though he can be stubborn and impulsive. He sometimes struggles with his destructive demonic power and fears hurting others. As Guest’s cousin, he cares about her and respects her strength as a fellow Knight. He is especially understanding of Guest’s mixed heritage because he also possesses two supernatural bloodlines.

One of the Four Knights of the Apocalypse and a member of the group traveling across Britannia. Small and youthful-looking with green hair, Percival is energetic, cheerful, curious, innocent, and incredibly compassionate. He often acts goofy or clueless but possesses remarkable courage and determination when his friends are in danger. His magical power, Hope, allows him to create mysterious magical beings and grants him incredible resilience. Percival quickly accepts Guest despite her demon-vampire heritage and sees her as a trusted companion and fellow Knight rather than judging her bloodline.