Tsukihi Araragi of Bakemonogatari, the main character of Tsukihi Phoenix, is one of Koyomi's sisters.
She's the youngest of the Araragi family. Unlike her sister Karen, she prefers doing indoor activities. Contrary to her personality, she constantly changes her hair style and is short-tempered to the point that Koyomi describes her as having hysteria. She revealed that she, unlike Karen, was not that invested in preserving justice and was just using Karen's vision to run wild. She is actually the reincarnation of a phoenix and has been since before she was even born. The phoenix entered the baby's body when it was still in the womb and by now both beings' minds have become one. She is immortal, except the only thing that can end her life is a natural death from old age. When she was a child, she fell down a building due to antics related to the fire sisters and was hospitalized and her body was covered with scars, though there are no traces of them now.
Voiced by: Yuka Iguchi