Inside the Kunie clan's base of operations in Akiba, Naotsugu and Henrietta look at the Royal Guard armor, where Enbart Nelreth is polishing one. After Shiroe and Naotsugu leave the city, Akatsuki passes him when he leaves Tatara's shop.
Sometime after that he left the Kunie Clan and stole some of the Mobile Armor equipment and had obtained the Sword Byakumaru. He started going on a killing rampage within the city of Akihabara using the sewers as place to conceal himself and goes on killing several players from different guilds including members from Soujiro's guild. Prompting Soujiro to go on and hunt the murderer for retribution.
Eventually Soujiro found him and fought against him one on one and later was joined by Akatsuki. Despite both of them being high skilled veteran players they were unable to do serious damage to him due to powers of the mobile armor and the powers of his sword. Even with shoryu's use of his over-skill technique he was still defeated, followed almost immediately by Akatsuki being defeated as well, after the battle he just taunted the defeated players and left, telling them Merry Christmas in a taunting manner.
Sometime later he was seen down the sewers and began to feel the effects of the Sword affecting him due to the flavor text of items starting to come into effect, and now is no longer operating under his own free will, instead being possessed by the vengeful spirit of Lugrius which was inside the sword.