Gyutaro was one of the primary antagonists in the Entertainment District Arc of Demon Slayer: Kimetsu no Yaiba. He was a demon affiliated with the Twelve Kizuki, holding the position of Upper Rank Six, a position he shares with his younger sister, Daki.

   Over a century ago, Gyutaro was a human child who worked as a debt collector in the Rashomon Riverbank of Yoshiwara, the lowest class in the Entertainment District, before he and Daki were turned into demons personally by Doma, who was Upper Rank Six at the time.

As a demon, Gyutaro was a relatively tall man of a somewhat muscular build with a black-dotted, pale grayish complexion whose anatomy was somewhat strange in that his upper torso, arms and legs were all extremely muscular where his waist was incredibly skinny, his pelvis jutting out at an unnatural angle. 

   He possessed thin, green and red eyes, their sclera bright orange, that were slanted drastically downwards at the sides, the kanji for “Upper Rank” and “Six” carved across them. He has unruly black hair that cut sharply off to a brighter green around the crown of his head, worn messily styled with uneven bangs and several ahoges. His body and face has noticeable ink-like markings in the form of black spots on his body and a flowing water-like pattern on his face. Gyutaro has been described to look very ugly.