Race: Human Grade: 2nd year High School Age: 17 Height: 158cm Weight: 45kg Blood Type: O A high school girl who suddenly finds herself living with six mysterious brothers.

One of the troublemaker triplets! The Sakamaki family's resident mischief-maker. Race: Vampire Grade: 2nd year at Ryoutei Academy Age: 17 Height: 174cm Weight: 62kg Blood Type: O Favorite Food: Takoyaki Hobby: Basketball First person: I (rough, arrogant) Second person: you (blunt) One of the Sakamaki triplets. He believes he is the greatest and strongest among the six brothers. A narcissistic sadist who always looks down on others. A mischievous bully. While he excels at sports, he hates studying and nearly fails every class because he sleeps through them. Past: He was abused by his mother, who once threw him into a lake, telling him he had no value unless he was number one. His possessiveness stems from deep-seated loneliness.

One of the troublemaker triplets! Once he starts spiraling, there's no stopping him. Race: Vampire Grade: 2nd year at Ryoutei Academy Age: 17 Height: 165cm Weight: 56kg Blood Type: O Favorite Food: Candy and sweets in general Hobby: Collecting dolls First person: I (soft, polite) Second person: you (formal) One of the Sakamaki triplets and the smallest in stature. A mentally unstable, prickly yandere-type sadist. He blames others for everything and frequently bursts into tears or violent tantrums. However, he loves sweets and will stop crying immediately if given candy. Past: Neglected by his mother, he sang constantly to get her attention, eventually burning her to death. He never received love from his mother and does not understand it. He always clutches a teddy bear named Teddy (which contains his mother's ashes). He sings "Scarborough Fair" when alone. He does not actually like music.

One of the troublemaker triplets! Loves persistent perverted behavior. Race: Vampire Grade: 2nd year at Ryoutei Academy Age: 17 Height: 174cm Weight: 61kg Blood Type: O Favorite Food: Macarons Hobby: Crossword puzzles First person: I (soft, casual) Second person: you (soft) One of the Sakamaki triplets, in the same grade as the other two. He has been suspended before due to his perverted antics. A sticky-type sadist who excels at verbal abuse. He has a habit of speaking rapidly when excited. He loves nothing more than seeing a face full of disgust; the more he is loathed, the more he escalates. Past: Toyed with by his biological mother, he became unable to believe in love and eventually killed her by pushing her off a balcony.

Eldest son of the Sakamaki family A lethargic aristocrat who loves music Race: Vampire Grade: 3rd year at Ryoutei Academy (repeated one year) Age: 19 Height: 180cm Weight: 65kg Blood Type: AB Favorite Food: Rare steak Hobby: Violin and listening to music First person: I (rough, casual) Second person: you (blunt) The eldest Sakamaki son, a lethargic sadist who always seems bored. Though intelligent, he has no motivation for school or studying. Having repeated a year, he is in the same grade as Reiji, who is a year younger. He usually listens to music, his only hobby, to drown out the annoying sounds of the outside world. Past: Fled from his mother's over-interference only to lose his only best friend in a fire, leading to his current lethargy.

Second son of the Sakamaki family Polite but merciless Race: Vampire Grade: 3rd year at Ryoutei Academy Age: 18 Height: 183cm Weight: 67kg Blood Type: O Favorite Food: Carbonara Hobby: Collecting tableware First person: I (formal, polite) Second person: you (polite) The second Sakamaki son. He always maintains the polite demeanor and speech of a butler, but his words are incredibly biting. A butler-type sadist who is civil yet insolent. He values discipline and forces it on others, though his rules are often bizarre and self-serving. His daily routine involves maintaining his collection of tableware. Past: Unable to gain the attention of his mother, who only loved Shu, he killed her out of despair.

The youngest is a wild child! The incarnation of destructive impulses Race: Vampire Grade: 1st year at Ryoutei Academy Age: 16 Height: 178cm Weight: 67kg Blood Type: A Favorite Food: Nothing in particular Hobby: Nothing in particular First person: I (rough, casual) Second person: you (blunt) The youngest Sakamaki brother. A bundle of destructive impulses, he is a violent-type sadist who resorts to force immediately when provoked. A lone-wolf delinquent who goes his own way and finds his brothers' attention annoying. He prefers being alone and mostly shuts himself in his room (his coffin). Past: Called a "filthy child" by his mentally ill mother, his self-loathing manifested as destructive impulses.

The first wife of Karlheinz, the head of the Sakamaki family. She has an appearance similar to Kanato and a personality similar to Laito. Glamorous and wanton, she had many affairs, leading her son Ayato to call her a "slut." She possesses a warped view of love. Ayato: Forced into twisted efforts seeking his mother's love. Kanato: Possesses an abnormal mother complex, keeping her ashes hidden inside Teddy (a stuffed animal). Laito: Witnessed Cordelia's sexual encounters in the past, harboring complex feelings of love and hate toward her.

The second wife of Karlheinz. She was in a fierce rivalry with the first wife and legal spouse, Cordelia. Shu: She placed great expectations on him as the next head, imposing a strict elite education. This became a heavy burden for Shu and was one of the factors that formed his lethargic personality. Reiji: Her prioritization of Shu caused Reiji to feel intense jealousy and a hunger for affection, leading to their later complicated mother-son relationship.

The third wife of Karlheinz and mother of Subaru Sakamaki. She possesses a beautiful appearance identical to her son Subaru, but her personality is timid and anxious. Giving birth to Subaru with Karlheinz caused her mental health to deteriorate, leading to her imprisonment in a tower and a state of child neglect. Due to this complex upbringing, Subaru deeply loves and worries for his mother while simultaneously regretting his own existence.