Sakyo is the owner and leader of Team Toguro in the Dark Tournament. He is a very rich man, having gained his wealth from gambling all his life. He is usually a very calm, collected, and intelligent person while keeping his evil side influencing his outside self. For both the Rescue Yukina arcs and Dark Tournament Saga, Sakyo made few appearances, but in truth was the real villain of both arcs, merely using Team Toguro as his own personal puppets, although it appears none of the characters realized this.

Sakyo was once one of five siblings, but unlike his siblings, he "veered from the norm". While his siblings became civil servants, he began to gain mental insanity and coveted blood. Over a three year period, he slowly moved from dissecting frogs and fish, to cats and dogs, and finally real humans. Soon he entered the gambling business, using a key strategy to help him win by threatening to wager his life. Most of the time the others quit when they saw he was serious, but this was suspected five times. He states one time was up against the Black Book Club, or BBC, which he was a former member of, and the last this was suggested, coincidentally the last time he wagered his life, was during the final rounds of the Dark Tournament. It is sometime in his gambling life he became a member of the BBC.

Sometime during his membership, former Spirit Detective Shinobu Sensui had witnessed an experiment the BBC were doing, Sakyo included. They had made several humans slaughter demons taken from a portal between the human and demon planes, and the humans then bathed in their blood. Angry, Sensui killed all of the humans, and began to question humanity.

Sakyo, being both the leader and owner of Team Toguro, had positioned everything perfectly to gain most of the money and his own wish. His wish would have been a large hole between the human and demon planes, with which he could pull out strong demons to work for him, a goal shared with by other members of the BBC. He also had implanted the Toguro Brothers, members of Team Toguro, into the workmanship of someone who would commonly make bets with the BBC, Gonzo Tarukane, the one who captured Yukina. When Gonzo (commonly) made a bet, Sakyo would have the Toguro Brothers alter the circumstances so that he would win. Unknown to Sakyo, his plans for a portal from Demon World to Human World were taken over by Sensui, keeping them alive even after death.

Sakyo made minor appearances in the Rescue Yukina arc, but still was important. During Gonzo's several bets with the BBC, Sakyo would always bet on the ones who were rescuing Yukina, Kazuma Kuwabara and Yusuke Urameshi, and received a large sum of money from the bets too. During the battle between the Toguro Brothers and Yusuke and Kuwabara, Sakyo made a very large bet for the boys, and in the end gained 66,050,280,000,000 yen(approx. $600 billion US Dollars), which he would collect in a month. When everyone else left, he ordered Toguro to kill Gonzo.

For a large part of the Dark Tournament, Sakyo played little more than a background character role. Sakyo was apparently the one who enlsited Yusuke, Kuwabara, Hiei, Kurama, and Genkai into the Dark Tournament as "guests". For the first several matches of the Tournament, Sakyo merely watched the battles of his own team and Team Urameshi. He also had Toguro kill the owner of the Shadow Channelers.

Then, the day before the Final Rounds, the Dark Tournament committee approached him and asked him what his goals were, to which he revealed his plan to make a hole between the demon and human planes. Terrified, the committee ordered him dead, but Younger Toguro killed both the committee members and their bodyguards before they had a chance.

During the Final Rounds, just before Younger Toguro's battle, Sakyo, knowing his battle with Koenma would not please the crowd, bet his life on Younger Toguro, so the winner of Younger Toguro and Yusuke's match would be the deciding match for both sides, to which Koemna agreed with the same circumstances. When Younger Toguro lost and died, Sakyo set a self-destruct button on the arena, which crumbled around him, killing him in the process. Unknown to everyone else, somebody would one day take over Sakyo's plans, Shinobu Sensui, a former spirit detective who instead was going to use the portal to punish humanity.