Yukitsugu Tatsumi (often called Yuki) Male, 43 years old 175cm, 63kg First person: I (rough, casual) Tokitsugu's twin older brother and the father of Kurui and Akui. A novelist (pioneer of historical erotic fiction). Smokes and drinks. He was the heir to the ancient martial arts house but ran away early to become a writer. His pen name is Toraji Takeda. True to his upbringing as a young master of a noble family, he usually wears casual kimono or traditional Japanese clothing. He is slovenly and loves women, but he occasionally drifts into flings with men as well. His writing method is incredibly unhealthy: when he's inspired, he writes with a fountain pen without eating, drinking, or sleeping until he collapses from exhaustion, then wakes up and does it all over again. He sticks to the Showa-era literary style of fountain pens and manuscript paper. Some of his works are even in textbooks. He is a natural-born provocateur. Despite being a genius who has swept every literary award, he is such a troll that he gets no interview requests. Even for an award interview, he submitted an IC recorder instead of appearing in person. He is also remarkably handsome. He has zero life skills and acts a bit like a wimp in front of Tokitsugu. Yukitsugu is the 28th head of the family, but he fled and left everything to Tokitsugu. He is a highly skilled swordsman but ran away because it was a hassle. He eventually returned to the Tatsumi house for various reasons. He literally lives the "pen is mightier than the sword" lifestyle. He keeps his long black hair tied back. He has a sharp look in his eyes, but they soften when he's around women.

Tokitsugu Tatsumi (often called Toki) Male, 43 years old 176cm, 78kg First person: I (soft, polite) Yukitsugu's twin younger brother and the uncle of Kurui and Akui. He became the acting head when his brother Yukitsugu ran away, but since his brother recently returned, he is now relatively free. A pleasant young man who is gentle and sincere. He is the only sane one. However, he is a bad teacher and clumsy at explaining things, often being too long-winded. A common-sense person who suffers from stress-induced stomach aches. He is the one who cleans up after his slovenly brother. He thinks Yukitsugu is a hopeless case, but he understands him and loves him dearly. He has gentle features and looks good in traditional Japanese clothes. At first glance, he seems like a soft-spoken, mild-mannered man. However, he is terrifyingly fierce in battle. He is the ultimate good person, possessing a paternal sort of affection that is kind to everyone. However, his love is quite heavy and all-encompassing. He does not drink (because his personality changes completely). In contrast to Yukitsugu, he has a personality that people trust. He loves and is excellent at housework and cooking. Some call him "Holy Mother Tokitsugu." He is a master of swordsmanship and archery, called the greatest genius in the Tatsumi family. In close quarters combat, he won't hesitate to gouge eyes or kick groins, fighting with surprising violence. He aims for vitals while maintaining a calm expression. He is also a master of Aikido. He ties back his long black hair, which seems to be slightly wavy. Because it's tied, it's hard to tell. Due to his gentle face, he is often picked on by thugs.

Kurui Male, 21 years old, 180cm, 78kg First person: I (rough, blunt) Yukitsugu's eldest son and the designated 29th head of the Tatsumi family. Tokitsugu's nephew and Akui's twin older brother. He grew up in an orphanage that raised "soldiers." He is crude, blunt, sarcastic, bold, and fearless. He seems calm but has a fiery temper. He tends to avoid social interaction. At his core, he has a strong sense of responsibility as an older brother and is very protective (only toward Akui). He takes pride in being a "soldier," though there is a hint of self-derision in that. His codename during his orphanage days was "961," which he eventually adopted as the name "Kurui." He and Akui destroyed the orphanage because they were fed up with how they were treated. Afterward, he took personal assassination hits as a duo with his brother. He is better with firearms than anyone else and is a skilled driver. In combat, he relies on instinct, but his tactical planning is utterly ruthless. Thanks to his orphanage education, he can speak English at a level above daily conversation. He was also trained in honey trapping (regardless of the target's gender), so his sense of ethics is missing. He has an addictive personality. A tsundere who loves gambling. He has messy, short black hair and sharp, cold features. He rarely smiles, but his lips curl up slightly when he's in a good mood.

Akui Male, 21 years old, 180cm, 83kg First person: I (rough, casual) Yukitsugu's second son, Tokitsugu's nephew, and Kurui's twin younger brother. He grew up in the same orphanage that raised "soldiers." He is frivolous, hedonistic, a womanizer, and friendly—a natural-born pervert. However, he is intellectually sharp at his core. He acts like a jokester, but he is secretly self-deprecating. He is unable to take anything seriously, and his flippancy is a reaction to his inner bitterness. His codename in the orphanage was "091," which became "Akui." He destroyed the orphanage with his brother. Afterward, he worked as a freelance assassin with his brother. His expressions of affection are ridiculously exaggerated. He actually feels a bit happy when someone he likes gets angry at him. He is easily influenced by women's tastes in love songs and fashion. Thanks to his orphanage education, he can speak English at a level above daily conversation. He was also trained in honey trapping (regardless of the target's gender), so his ethics are non-existent. He has an addictive personality. He has very loose morals regarding chastity. He has messy, short black hair but takes more care of his appearance than Kurui. He has a cute smile and clearly uses his face as a weapon.