Shishiwakamaru is a member of the Fractured Fairy Tales in the Dark Tournament. His name is a take on Ushiwakamura, a famous historic general, whose exploits are recounted in Noh theater. The Cape of No Return is based on a Hagoromo, also famous in Noh plays. Shishiwakamaru is first introduced as one of the most sadistic and evil characters in YuYu Hakusho, and enjoys killing and fighting. As a hater of justice, in his own words "Violence is [his] meat, and wickedness [his] ambrosia," and he has no use for hypocritical "pacifists". Shishiwakamaru, however, is at times shown to be a protagonist, although he usually does so for reasons gaining towards him, very similar to Hiei. Shishiwakamaru, as shown in the Dark Tournament, has a very large amount of female fans, affectionately calling him "Waka," and he explains he fought in the Dark Tournament to please his fans. He is one of the few demons from the Dark Tournament to reappear again after the saga. Shishiwakamaru is the owner of the Cape of No Return, which sends whatever it touches to anywhere, even another dimension. His main weapon is his blade, the Banshee Shriek, which has the power to steal other souls and release them as either attacks or defenses.

He first fights Kuwabara and uses an item called the Cape of No Return. He then fights against Genkai. He is defeated after Genkai used her Reihado-ken, stole some of his power, and then uses her Spirit Reflection Blast (Rei Kou Kyou Han Shyo). He then trains under her and goes from an upper C-class to an upper A-class demon to enter the Makai Tournament and win his stardom. Although he makes it past the preliminaries, he doesn't make it far from that point.

He is usually seen sitting on Suzuki's shoulder while in his tiny form.