Nakatsukasa, Tsubaki

中務椿

She serves as Black Star's partner for the Dark Demon Blade. She is capable of transforming into various ninja weapons, such as shuriken, smoke bombs, and a katana (in later chapters), among others. Although Black Star's loud demeanor often disheartens her, she tolerates it because that is precisely what she likes about him. She possesses a very forgiving personality and consistently attempts to assist everyone, even when she has no idea how to help. According to Dr. Stein, Tsubaki's soul is "very co-operative and has a lot of space to accept people".