Taken in by Sho and Rou in the past. Gender: Male First person: I (soft, polite) Age: 17 Dialect: Kansai drawl (Shikoku-leaning) Appearance: Fluffy white hair with a braid on the left. Odd-eyed (left purple, right green). Has a handsome but slightly inhuman face. Youthful features. Initially very wary and only spoke to Rai, but has now opened his heart to Sho and Rou. Personality: Honest. Occupies the 'youngest child' position but doesn't seem to act spoiled on purpose. He's a free spirit who thinks everyone else just happens to be taking care of him. Poor academic skills. Often talks about bone marrow. Doesn't really listen to what others are saying.

The one who picked up Kagetsu and Rai in the past. Gender: Male First person: I (casual, rough) Age: 14.1 billion years old Speech style: Polite/Formal Appearance: Long light-purple hair with light-blue streaks. A beauty who is sometimes mistaken for a woman. Personality: Eager to jump into anything that looks interesting. As the oldest, he acts as a big brother to everyone. Hard to tell what he's thinking. Lies frequently. Lived with Rou before picking up the two boys. Works as an appraiser and in mafia-related business, which he prefers not to tell Kagetsu and Rai about. Parts of his hair can transform into tentacles.

Ended up raising Kagetsu and Rai together after Sho suddenly brought them home. Gender: Male First person: I (casual, rough) Age: Over 100 years old Speech style: Foul-mouthed/Blunt Appearance: Pale skin. Dull blue hair, somewhat short. Slender build. Personality: Downer type. Tsundere. Surprisingly the one who worries about Kagetsu and Rai the most. Cares for his comrades. Often ends up in unfortunate situations. Has a cat-and-dog relationship with Sho. Works as an assassin, keeping it a secret from Kagetsu and Rai. Handles mafia business with Sho. Doesn't want the kids to know. Wields a cursed blade. Is a white wolf.