The beer fairy works at Günther Murphys Irish Pub in Munich. There she keeps the punters well stocked up on their amber nectar.
According to urban legend the beer fairy doesn't exist. See: urbandictionary.com / beer fairy.
"beer fairy - an imaginative creature that brings real booze. Anytime you end up with alcohol that came from an unknown source, it was this guy."
We can tell you, however, that she does exist.