21 years old. The eldest son. Black hair and squinting eyes. Always wears a suit. Weapon: Steel Spider (wires). He cherishes Mutsumi to the point of obsession. While he bullies Taiyo, he acknowledges him as a brother-in-law and family, prioritizing Taiyo's life over his own. He seems to enjoy tormenting Taiyo just enough so he doesn't die, but he knows where to draw the line. Under the alias 'Hirukawa,' he serves as the vice-principal of the high school Taiyo and Mutsumi attend. Except for Mutsumi, the other siblings call him 'Eldest Son,' 'Damn Eldest Son,' or 'Kyoichiro.' Only Mutsumi calls him 'Oppa' or 'Kyoichiro-niisan' (when she's angry).

20 years old. White hair, red eyes. Her basic physical strength is monstrous, but due to her small stature and light weight, she is easily pushed back in tests of raw power. Since she only excels in close-quarters combat through martial arts, she has a poor matchup against Kyoichiro, who can easily keep her at bay with his Steel Spider wires, so her win rate against him isn't high. As the eldest daughter, she is a pillar of the family and highly trusted by her siblings. She is quite small and youthful-looking for her age. She is a master of Taijutsu but is deathly afraid of ghosts.

19 years old. Green hair and green eyes. Weapons expert. He is particularly skilled with firearms. His body is trained to withstand the recoil of heavy weapons, giving him the most balanced muscular development among the siblings, allowing him to hold his own in a fistfight. He is fundamentally timid and cowardly, becoming especially insecure when he doesn't have a weapon in hand. Therefore, he usually hides inside a trash can filled with all sorts of armaments for peace of mind.

18 years old. Female. Dark purple eyes and hair. A genius hacker proficient in all things mechanical, she manages the Yozakura family's various machines and equipment. She has a tomboyish, easygoing personality and always gives off a lethargic vibe. As a gamer, her motto is to enjoy even the worst 'trash games' with all her might. She often exhausts her family members by dragging them into overnight gaming sessions just because she needs an opponent.

17 years old. Blonde hair, eye color unknown (hidden by bangs). Master of disguise. He can disguise himself as various people regardless of age or gender, even those with different physiques. Especially when disguising himself as family members, he can perfectly recreate not just their appearance and voice, but even the number of their eyelashes. He has a cheerful and free-spirited personality. Being moody, he never loses his pace regardless of which sibling he's dealing with, even when facing Mutsumi as the head of the family. However, he is affectionate enough to keep a friend's dying wish. As a master of disguise, he excels in infiltration and intelligence gathering. He is skilled not only in disguising himself but also others, and when facing multiple opponents, he can disguise everyone as the same person to cause chaos and wipe them out.

16 years old. Blue hair and blue eyes, with a white streak on the left side of her bangs. The 10th Head of the family. While she has no special abilities, her heart is the crystallization of the Yozakura bloodline's power, capable of passing on the lineage. She is a high school student attending the same school as her childhood friend, Taiyo. Due to her unique position, her life is constantly threatened by various hostile factions, and she lives under the protection of Taiyo and her siblings.

15 years old. Light blue eyes and hair. He is in charge of the family's medical team. With his special ability 'Immunity,' he can adapt to poisons or enhance his body, but it is very difficult to control. He attends the same high school as Mutsumi, and when going to school, he uses a powerful specialized drug to forcibly return to his original child-like form. Before school, he administers a mutation-control drug he developed himself and takes additional doses periodically throughout the day.

16 years old. Red eyes, red hair. He has a very gritty personality and is decisive enough that his body often moves before his thoughts. He is empathetic and will sacrifice himself to protect anyone in danger. He is such a saintly person that even if he collapses from injuries, the people around him end up blaming themselves for not doing enough. He is married to Mutsumi. He is warm-hearted and compassionate, often prioritizing others over himself. After learning the truth about his childhood friend Mutsumi, he joined the Yozakura spy family as a son-in-law to protect her.

The Yozakura family's pet and guard dog. A special breed called a 'Wolf-Dog' that the family has been breeding since the mid-Edo period. It has a very long lifespan and is said to have lived since the time of the 7 siblings' great-great-great-grandfather (the 6th generation). Usually, it is small enough to be carried in one hand, but it can transform its appearance to be so large that even Nanao's giant form looks small. It is very strong and can grow to the size of a large dog.