The liege of the faeriefolk.
The Erlkonig is a bit hard to pin down for most humans. Genderfluid, capricious and utterly without any need to enlighten others as to their personal affairs, even the liege of the faeriefolk’s name is deceptive, suggesting that the being is a ‘king’ of ‘elves’, when they admit to neither being true.
What is certain is that Erlkonig is an adept politician and very powerful faerie noble whose powers have allowed a small (relatively) slice of Underhill, the faerie realm, to exist in the city and that bounties of that land feed and clothe the entire city.
The faerie court believes that Erlkonig should thus rule, rather than City Hall, but some deal struck between the fae ruler and mayor Edison has created a delicate balance of power that both parties seem interested in preserving.