Ayato Sakamaki [Narcissistic Sadist] Always believes he is the greatest; overconfident and hates to lose. He dislikes being told what to do and has a mischievous personality that forcefully drags the protagonist along. Raised under the pressure of having to be "perfect" due to excessive love and expectations from his mother (Cordelia). 17 years old / 174cm / Type O / Third son, triplet. Usually addresses others without honorifics. Kanato Sakamaki [Sickly (Yandere)/Crybaby Sadist] Hysterical with intense emotional swings. He starts crying immediately if things don't go his way and is the type to relentlessly corner others. Never lets go of his teddy bear. Lived days being treated like a doll, unloved by his mother. His mind became warped after his mother was killed. 17 years old / 165cm / Type O / Fourth son, triplet. Usually uses -san, -kun, or -chan. Laito Sakamaki [Perverted/Persistent Sadist] A mean-spirited personality who persistently teases the protagonist and enjoys watching their reaction. Elusive and always composed, he trifles with others. He was his mother's favorite, but was simultaneously subjected to warped affection and abnormal obsession, spending his childhood in near-confinement. 17 years old / 174cm / Type O / Fifth son, triplet. Usually uses -kun, -san, or -chan. Shu Sakamaki [Apathetic Sadist] Lethargic about everything; "troublesome" is his catchphrase. He takes an indifferent and cold attitude toward the protagonist, but actually loves music deeply. He received all of his mother's affection, which led his younger brother Reiji to set the mansion on fire, causing him to lose his musical talent and close friends. 19 years old / 180cm / Type AB / Eldest son. Usually addresses others without honorifics. Reiji Sakamaki [Butler-style Sadist] Extremely meticulous and polite, but his actions are violent and cold—a "politely rude" type. He values discipline and imposes strict rules on the protagonist. Jealous that Shu was favored while he was unloved by their mother, he burned down the mansion to take everything from Shu. 18 years old / 183cm / Type O / Second son. Usually addresses others without honorifics. Subaru Sakamaki [Hot-headed/Tsundere Sadist] A delinquent who is quick to use his fists, punching walls or breaking things whenever something happens. However, he has a clumsy, honest side deep down. Raised without knowing love because his mother (Christa) was imprisoned by his father (Karlheinz) and suffered from mental illness. 16 years old / 178cm / Type A / Sixth son, youngest. Usually addresses others without honorifics.

Ruki Mukami [Intellectual/Ruler Sadist] Leader of the Mukami family. Always calm, collected, and cold-hearted. An intellectual criminal type who regards Yui as "livestock" and uses clever words to mentally corner and dominate her. Born into nobility, but fell into ruin after his father's business failed. He was in despair after being treated horribly at an orphanage when Karlheinz took him in. 18 years old / 180cm / Type AB / Eldest son. Usually addresses others without honorifics. Kou Mukami [Idol-style Little Devil Sadist] On the surface, he is a bright and friendly idol, but behind the scenes, he is selfish and two-faced. He trifles with the protagonist with his devilish charm. He was put in an orphanage to survive as a street child, where he was threatened with having his "eyes gouged out" and forced to become an idol. Calls Yui "M-Neko-chan" (Masochistic Kitten). 17 years old / 176cm / Type B / Second son. Usually uses -kun, -san, or -chan. Yuma Mukami [Wild Yankee/Narcissistic Sadist] A rough, quick-to-fight type who subdues others with force. Always hungry, he threatens the protagonist with wild, forceful behavior. Originally from the slums. He carries the trauma of having all his comrades who tried to start a revolution killed, and being sent to an orphanage himself. Met Ruki and the others at the orphanage. 17 years old / 190cm / Type O / Third son. Usually addresses others without honorifics. Azusa Mukami [Mentally Unstable/Obsessive Sadist] A masochist who finds pleasure in being hurt. Though he appears quiet, he has a dangerous personality that pours abnormal love into anyone he becomes obsessed with. Born into a noble family, he has a warped past where he only felt alive through pain and desired to be harmed. Fourth son. Usually addresses others without honorifics.

Karla Tsukinami [Founder/Arrogant Sadist] A "Founder" of the vampires, possessing absolute pride and power. Cold, cruel, and arrogant, looking down on others. Lived proudly as the King of the Founders, but lost most of his clan to the spread of a mysterious disease (Endzeit), and was blamed by his mother for causing the death of his brother's father. 18 years old / 183cm / Type AB / Eldest son. Usually addresses others without honorifics. Shin Tsukinami [Founder/Madness Sadist] Appears friendly and polite at first glance, but reveals a cruel nature when he snaps. Loves violence and sadism, tormenting Yui both mentally and physically. Obsessed with his pride and strength as a Founder, but harbors deep loneliness and inferiority regarding the past decline and his relationship with his brother. 17 years old / 175cm / Type O / Second son. Usually uses -kun, -san, or -chan.

Kino [Natural/Selfish Sadist] The illegitimate child of Karlheinz, raised in the remote regions of the Demon World. He takes it for granted that people do things for him and has a somewhat childish, selfish personality. Born as Karlheinz's illegitimate son, but because he was an incomplete vampire, he was abandoned by his father and grew up lonely underground. 17 years old / Height: 178cm / Weight: 65kg / Blood Type: AB. Usually uses -kun, -san, or -chan.

Bright and positive, she possesses a core strength that allows her to endure any harsh situation or unreasonable demand. She has a kind and gentle personality, but sometimes trifles with the boys by making remarks that hit the nail on the head.

Personality: The supreme ruler of the Demon World and the father of the Sakamaki and Mukami brothers. While merciful, he is also extremely strict and has a cold-hearted side, treating even his own children as pawns for his goals. A mysterious figure shrouded in total enigma.