Mudai was a tall man, with purplish blue, long hair tied into a tail. He wore tunic from white cloth. Mudai like other gravekeepers collected skulls. He had five of them.
Before the creation of the retribution group, Mudai was one of the guardians of the tomb of the first emperor in Putra. While he was on the other mission all of the guardians were killed by Elite Seven. He decided to avenge his friends. Mudai took Najasho, which he found in a ruined tomb, as his bodyguard and he had gone to find other people that will want to eliminate his friends' killers.
After gathering other people, with the same goal, Mudai teamed with Suzaku - head of White Horse clan, what gave the beginning to Retribution Group. They decided to stay on Hakuba mountain. After Empire learned about the existence of their group, they sent Elite Seven to eliminate them. Mudai used Najasho to lure some of the members out of the city and they started to fight. During the battle, Mudai was protected to the end by Najasho. During the fight, they lost Mila. When other members of Elite Seven came, Mudai's group decided to flee from the battlefield.