Had an idea that gave me a chuckle, given the other game we have together Bella. Tell me what you think.
Bio: According to the official series of events the Queen of Vampires had tired of the constant badgering to take a king, or at least a consort, from among men under her dominion. Finally having had enough of this nonsense, she did what was thought to be impossible just to prove a point.
What she had done was summon an Incubus, a demon that used supernatural animal magnetism to lure in and feed on the lifeforce of women. The demon, who was supposedly sexually irresistible to all sentient females, had attempted to use this to force the queen into being it's servant- but through sheer force of will the queen turned this back onto him and enslaved him instead. Presenting him to the court, her challenge was that she would take as a consort any man who could surpass an the Incubus in actual usefulness and not before. The challenge has yet gone uncountered.
But that's only the official recording of events. What really happened was completely different. Hell, they didn't even get all the facts about what in Incubus was correct. Among the abilities of Incubi and Succubi is the ability to switch genders at will, they themselves only tend to stick to one gender to ease how they operate. A Succubus prefers behind the scenes manipulation and drawn out seductions while in Incubus prefers more direct approaches to it's problems- at least in comparison to a Succubus as both tend to be incredibly devious. The "feed on lifeforce during sex" thing? Really, they can do it in any situation where there's a symbolic bond of trust or prolonged physical contact- during sex is just the most fun.
The Queen, desperate to consolidate her power base, had attempted to summon allies from down below. However, in her desperation, she had made mistakes in the summoning- something which traditionally meant the demon was obligated to kill her. For a laugh they had sent an Incubus to drain her of her life force completely. Fortunately, while the queen was desperate she wasn't stupid and had planned for this possibility to further an ally into power. Impressed with the cunning displayed, the Incubus stopped short of killing her and seeing in opportunity for himself became a partner in crime in her political maneuvers.
So publicly, he's almost literally a boytoy for the queen as well as a very visual message about her arcane strength and will power. In private however, he's an absolute demon who enjoys the idea that the woman who pretty much rules the world calls him "master" and helps him procure other women to feed from.