He is voiced by Takeharu Onishi in the Japanese version of the anime and Troy Baker in the English version.
Madarao's fur is snow white; his eyes are pale green with a slightly dark green color for the pupil. Two thin black circles surround his pupil. He displayed noticeable features, such as the black outline around his mouth, which contain his jagged, sharp teeth. In addition, on his tail he has three gray circles surrounded by a dot. He wears a purple "collar" that is designed to seal away his true form. Pink clouds follow him to indicate that he is undead. Normally, his body is much like a snake; a head, body, and no legs, but at certain times, two front legs appear, which he uses to "run" in the air.
In his released form, he grows ten times bigger and takes the form of his former self: a massive demon-wolf. His circles remain intact on his back and tail. He also has some green lines near his eyes (like the purple lines near Kouya's eyes in his true form) in his true form.
Though highly experienced in hunting Ayakashi, Madarao tends to be lazy or selfish when the mood strikes him. He is generally unsatisfied with having Yoshimori for a partner, but would rather work with him than look bad in comparison to Hakubi, who is younger and less experienced. Madarao enjoys eating small Ayakashi, insulting Hakubi (and the Yukimuras), (playfully) scolding or teasing Yoshimori, and sleeping. Madarao has stated numerous times that he "fell in love" with Tokimori Hazama, and that "love knows no gender or species", implying that he is homosexual.
Madarao's Japanese consists of many set phrases and parts of speech that are normally used only by women, thus many had assumed he was female since his speech mannerisms was the only information they had. In an early tankoban omake, the manga artist tries to clear up the confusion by stating that Madarao is not only male, but is in fact gay—something that was always the case since the series one-shot was published. Madarao's devotion to Tokimori is absolute. Shigemori Sumimura values Madarao's opinion, and occasionally has him evaluate Yoshimori's progress.
- His English Voice Actor, Troy Baker also voices Yamato from Naruto Shippuden Episodes 34-229, Excalibur from Soul Eater and Greed from Fullmetal Alchemist: Brotherhood.