Tsukihi Araragi is the supposed younger sister of both Koyomi Araragi and Karen Araragi, and the youngest member of the Araragi family. She is the younger half of the Tsuganoki Second Junior High School's Fire Sisters. She is unknowingly an offspring of the Shide no Tori, making her a fake human and giving her traits similar to that of a phoenix. She is nicknamed Rara by her childhood friend Nadeko Sengoku. She is the titular protagonist of two main arcs: Tsukihi Phoenix and Tsukihi Undo, and of two minor arcs: Tsukihi Eternal and Tsukihi Brushing. Tsukihi appears to be a young girl in her early teens with black hair and dark gray irises. She wears a sunny side-up egg-shaped hair clip on the side of her hair like her older sister Karen, although Tsukihi has hers on her left side. Like the other Araragi siblings, she has an ahoge. She also has a habit of changing her hairstyle constantly. Her wardrobe almost exclusively consists of bright-colored yukatas and kimonos which vary in length. Unlike her sister Karen, she prefers doing indoor activities. Contrary to her personality, she is short-tempered to the point that Koyomi describes her as having hysteria. Rosokuzawa is mentioned to be Tsukihi's boyfriend by her brother, and she says she's in love with him but has a chaste relationship. Despite being a member of the Fire Sisters, Tsukihi admits that she doesn't have the drive to do things like her older sister, although she says that she shares her siblings' belief in justice. She's also a bit airheaded at times. Also like her sister, she doesn't believe in oddities or the supernatural, despite being one herself.