He is the oldest adopted son of Ryuken, elder brother to Toki and Sayaka and the younger brother of Kaioh. He was born on the island of Shura and was sent by Jukei along with Kenshiro and Toki to train under Ryuken. When they met, Ryuken originally wanted to train one of the two brothers, but Raoh demanded that he take both of them under his wing. Like Kenshiro, Raoh had a heart for Yuria. After Kenshiro became the successor, Raoh decided to make his dream into an ambition. He started this by killing Ryuken. Raoh then vowed that he would master all martial arts and rule the heavens. To that end, he built an empire becoming Ken-Oh.
After the destruction of Cassandra prison, Raoh went to Mamiya's village to challenge Rei, then Kenshiro. The fist king ended his fight with Rei easily by striking the Shinketsushu power point. Raoh's second round in Mamiya's village was against Toki until Kenshiro stood up. During the fight, Kenshiro discovered that Raoh had used techniques of other martial artists. In the stalemate that followed, Raoh promised to see Kenshiro again. In the war with Souther, Raoh helped out Kenshiro and fought some of the emperor's lackeys. When Souther died, Raoh continued to recover.
After his recovery, Raoh fought with Ryuken's past rival Koryu and killed him. Toki then decided to keep his promise to stop Raoh personally and they fought in a field. As Toki began to die of his radiation poisoning, Raoh let him go as a civilian. Raoh's lieutenant, Ryuga at first saw his master as a savior, but in the battle with Kenshiro, Ryuga decided to end his own life along with Toki's.
Raoh then sought out the last Nanto general. The elder Hokuto brother fought through the first 3 of the Goshasei, Hyui, Shuren and Juza along side his army. In the battle with Juza, Raoh discovered that Yuria is the last Nanto General and is alive. Kenshiro met his adoptive brother again in the Nanto general's castle and Kenshiro showed off the Musou Tensei technique. Now with fear, Raoh retreated with Yuria in his hands at last. Raoh later then fought the other surviving Goshasei fighter, Fudo. While Raoh lost due to his fear, his men mercilessly killed Fudo with ballista shots. Raoh noticed the misfiring and took his anger on his men. Raoh went home and saw Yuria was dying of radiation, and for once, he sympathizes with her situation, sharing her sorrow of her sad fate. This would enable him to also master the Musou Tensei. Raoh then put her in a coma to stop the disease spread. Kenshiro and Raoh fought their final battle at the Hokuto Renkitoza where they first met Yuria. After the final battle, Raoh then killed himself with no regrets of his life.
Near the very end of the manga, it is revealed that his has a single, illigitimate biological son named Ryu, who Kenshiro takes under his wing.