Tsubaki Nakatsukasa (中務 椿, Nakatsukasa Tsubaki) is a Demon Weapon originating from the ancient and special Weapon clan, the Nakatsukasa Clan. She is the daughter of Sanjuro Nakatsukasa and the younger sister of Masamune Nakatsukasa. She joined DWMA in an effort to stop her brother from becoming a Kishin and later partners up with the assassin student, Black☆Star. She is known as the "Demon Shadow Weapon (魔暗器, Maanki; Dark Arm in english dub)" and was a former member of Spartoi. She is one of the main protagonists in Soul Eater.