Artemis is a bartender who is the owner of The Confidential, a secret bar for Springfield bartenders. He made his first (and so far only) appearance in the Season 32 finale episode, "The Last Barfighter", and is voiced by Ian McShane.
Artemis is the owner of The Confidental, where Moe hangs out with other bartenders. He spoke to Artemis about his day and told him all the secrets he had been told by his barflies. When Moe had a drunken night out with his friends and exposed secrets about other bars' patrons (as well as his friends), he got kicked out of The Confidential and his regulars were to be "cut off" - injected with the anti-booze at "Happy Hour", 5:00pm, which prevents them from having to drink alcohol again.
Three months after Barney, Carl, Homer and Lenny got injected with the anti-booze, they showed their loyalty to Moe and returned to Moe's Tavern. Artemis appeared, being pleased with their loyalty and rewarding them with the antidote. While Barney, Lenny and Carl decided to inject the antidote, Homer refused because he never got to be the person he wanted to be. Artemis and Moe then called bartenders to inject Homer with the antidote.