The bartender at an online bar frequented by killers including Elca and other shady members of the black market. He is extremely capable, even against skilled killers. He is an NPC, likely a highly advanced AI, who was discarded by his creator, who considered him a failure. He now works for Myung-Gun in an undefined role, though Myung-Gun describes him as his "supporter" and he seems to function, among other things, as a bodyguard. Lotto originally thought "J" may stand for joker. He claims to have no true name, but has always been called "J". He is also extremely powerful.