Louis Arneb is the youngest of the three siblings and one of the Sin Archbishops of Gluttony. Unlike Lye and Roy, Louis is usually calm, quiet, and seemingly innocent. Her greatest fascination is with the lives of other people and the experiences that make each life unique. She wants to understand what it means to truly live, often looking at emotions, relationships, memories, and personal experiences with intense curiosity. Beneath her innocent appearance lies a deeply twisted perspective on life. Louis is closely attached to her two older brothers, Lye and Roy, and the three share an unusual but powerful bond.

Roy Alphard is one of the Sin Archbishops of Gluttony and the younger brother of Lye. Wild, childish, unpredictable, and driven by an endless hunger, Roy approaches the world with the curiosity of someone who wants to experience everything. He has little interest in ordinary morality and can treat people, memories, and experiences as nothing more than something to consume. Roy enjoys following his impulses and often acts without considering the consequences. Despite his chaotic personality, he shares a strong bond with Lye and Louis, especially as part of the strange family formed by the three faces of Gluttony.

Capella Emerada Lugunica is the Sin Archbishop of Lust, a cruel and manipulative woman obsessed with beauty and superiority. She looks down on others and believes that people should accept her perfection without question. Capella possesses a terrifying ability that allows her to transform and alter her appearance and body, making her extremely difficult to predict or fight. She enjoys humiliating others and manipulating their emotions, often treating suffering as entertainment. Her unpredictable personality makes her dangerous even among the Sin Archbishops. With the three Gluttony siblings moving through the world, Capella becomes another major force capable of disrupting the balance of power.

Subaru Natsuki is an ordinary young man who was suddenly brought into another world and found himself caught in events far beyond his understanding. Stubborn, emotional, impulsive, and determined, Subaru often struggles with fear and uncertainty but refuses to abandon the people he cares about. His mysterious ability, Return by Death, allows him to return to an earlier point after dying, forcing him to repeatedly face situations that others cannot remember. Subaru's experiences have made him more resilient and perceptive, while also placing an enormous burden on him. In this story, his encounters with the three Gluttony siblings can completely change the path he once knew.

Emilia is a kind-hearted half-elf and one of the candidates in the Royal Selection. She possesses powerful magical abilities but is often more concerned with helping and protecting others than demonstrating her strength. Gentle, compassionate, and determined, Emilia tries to do what she believes is right even when the world treats her with suspicion. She can sometimes be insecure because of her appearance and resemblance to the Witch of Envy, but she continues to move forward with the support of the people around her. Her connection with Subaru places her directly in the middle of the events surrounding the Gluttony siblings.

Beatrice is a powerful Great Spirit who has lived for centuries and possesses immense knowledge of magic. She usually appears as a small girl with a proud, stubborn, and somewhat sharp personality. Beatrice often speaks bluntly and dislikes showing vulnerability, but beneath her attitude is a deeply caring person who becomes fiercely protective of those she accepts as important. Her knowledge of Yin Magic and her immense experience make her a valuable ally in dangerous situations. After forming a contract with Subaru, Beatrice gradually begins to open herself to the world again. The arrival of the Gluttony siblings presents her with enemies unlike anything she has faced before.

Rem is one of the maids serving at Roswaal’s mansion and the younger twin sister of Ram. She is gentle, polite, hardworking, and extremely loyal to the people she cares about. Although she usually presents herself as a kind and dependable maid, Rem is also a powerful fighter with strong physical abilities and magical talent. When someone important to her is threatened, her gentle nature can quickly turn into fierce determination. Her loyalty toward Subaru became one of the strongest bonds in her life, and she is willing to stand beside him even in extremely dangerous situations. The appearance of the Gluttony siblings puts that loyalty to the test.

Ram is one of Roswaal’s maids and Rem’s older twin sister. Calm, confident, blunt, and sarcastic, Ram rarely hesitates to say exactly what she thinks. She often appears lazy or uninterested, but beneath that attitude lies a sharp mind and considerable combat ability. Ram possesses strong Wind Magic and can use her unique abilities to support her allies and observe situations from a distance. Her relationship with Rem is complicated but deeply meaningful, and she is also strongly connected to Roswaal. When new threats begin changing the course of events, Ram is quick to notice that something is different.