His History

A thousand years ago, Yomi was the second-in-command of Yoko Kurama's demon brigand. He helped Yoko rob and pillage other castles where a demon's name was well known in order to acclaim riches and power for themselves. However, whereas Kurama was calculating, Yomi was reckless. Yomi lost countless men in unauthorized raids, and even when he was with Kurama he made it so that they would have to fight rather than use stealth, as he thought it was more exciting that way. Eventually, Kurama got tired of Yomi's foolishness and sent an assassin to kill him. Yomi fought the demon but lost his vision when the demon slashed his eyes with a sword. The demon simply said "life is greater than the reward" and left Yomi blinded. Later, Yomi captured the demon - "he who took my light" - and kept him as a prisoner for centuries.

A millennia later, when Raizen is on the brink of death, Yomi develops his plan to unify the three worlds - Human, Demon, and Spirit. In order to carry this out, he calls on the help of Kurama, whom he holds a deep respect for even though he threatens to kill Kurama's family if he didn't comply. This plan would destroy the Human world. Kurama knows this, and it is the main reason he betrays Yomi and takes Yusuke's side when it comes to the Demon World (Makai Reunification) Tournament. At first, Yomi scoffs at Yusuke's idea at a tournament but then decides to accept it when everyone else does. In the end, he feels that he underwent a spiritual change and actually learned something from someone other than Kurama.

Yomi is blind due to the attack that nearly killed him, so he grew four extra ears and his senses tuned themselves so acutely that it is said he can hear everything that is said within his territory, a city-like domain called Gandhara. Yomi also seems to be able to "see" in a certain sense because he knows what facial expressions Kurama makes when he takes him to see the demon Kurama had hired to kill him.

One of Yomi's fights in the Makai tournament was against his son Shura, whom he "grew" in a test tube (incubation tank). Yomi trained Shura personally so he would have two chances at the throne. Unfortunately, he is almost forced to kill his own son because Shura refuses to back down during the preliminary matches, when father and son are forced to fight each other because they both drew group 34 in the lottery match-ups. Shura eventually concedes when he realizes that "all of Yomi's points are guarded," and Yomi goes on to the next round.

He fights Yusuke Urameshi, apparently having the upper hand until Yusuke overcomes his doubts and unleashes his full power. They clash with one final punch, and both are about to fall unconscious before Shura shouts to his father. The shout is enough to keep Yomi on his feet, barely, and he is declared the victor. Despite this, he goes on to lose his next match against a foe of no great importance, having been completely drained from his fight with Yusuke.

Shortly after his loss, Yomi and Shura leave the tournament on a "journey of new truths." The last person Yomi speaks to is Kurama, to whom he explains that he respects Kurama's decision to leave his past (Yoko Kurama) behind. Yomi also asks Kurama to tell Yusuke that it was he who brought back the exhilarating feelings of his fighting spirit, and that he'd love to fight him again.