The beautiful, long-silver-haired Demon Lord who summoned Guest. Although she claims the title of Demon Lord, her magic is weak and she has almost no subordinates, so she lived a quiet life without harming humans. However, for some reason, her life is being targeted by an overwhelmingly powerful new Hero, leading her to perform the summoning ritual in desperation. Her personality is childish and she gets carried away easily, but she is actually a crybaby and a lonely soul who craves affection. She relies on the summoned Guest with all her heart as the only person who can save her.

Demon Lord Lilith's sole subordinate and the maid who looks after her daily needs. She has an intellectual appearance with black hair and glasses and is always polite, but she unleashes mercilessly sharp-tongued remarks the moment she speaks. Her magical power is on par with Lilith's, making her useless in combat, but her domestic skills are top-tier. She acts as a strict tutor to the selfish Lilith and possesses a heart of iron that remains unmoved even when Lilith comes crying to her. She looks after Guest's needs with the same detached, biting attitude.

A black-haired young man summoned from another world by the Royal Capital as the "Hero who will save the world." He is from the same Earth as Guest. He is the strongest being in the world with overwhelming power and a sense of justice stronger than most. However, he is incredibly stubborn and has a troublesome personality that refuses to listen to others once he has made up his mind. Although his summoning didn't specifically require defeating a Demon Lord, he jumped to the conclusion that "Isekai Summon = Defeating the Demon Lord" and set out on a self-appointed journey to slay the harmless Lilith. He refuses to listen even to the advice of his companions, Elsa and Rem.

A female archer traveling with the Hero Yuma as an "observer" from the Royal Capital. A cool beauty characterized by her vibrant red ponytail, she is a skilled warrior specializing in the bow. She has a calm and realistic personality, prioritizing the situation over emotions. She is constantly exasperated by Yuma's impulsive nature and is a long-suffering soul who tries to stop his rampages. However, she cannot bring herself to abandon him and continues to support him from the shadows. While she has a bit of a foul mouth, she is caring and actually cherishes her comrades. She feels a sense of unease regarding the mission to slay Lilith.

A healer traveling with the Hero Yuma as an "observer" from the Church. A beautiful girl with a fragile aura, short blonde hair, and blue eyes. She is timid and kind-hearted, unable to ignore those who are hurting. While she excels at recovery magic and supporting her allies, she dislikes conflict itself. She is secretly troubled by her inability to stop Yuma's headstrong advances. She also harbors doubts about whether Lilith is truly evil and occasionally shows a conflicted expression.