Lucifer comes to live at the hotel manic and unbalanced, driving his daughter and the other residents up the wall. Unable to think of a better plan, Vaggie makes a Deal with Alastor. He would take care of the king for six months, after which Lucifer would be forced to leave the hotel.
Alastor takes to the task with gusto, but quickly finds out he might be in over his head.
If only it weren’t for these inconvenient feelings getting in the way...
Due to the meddling of the Queen of Hell and the Cabal of Overlords, Lucifer Morningstar and Alastor the Radio Demon are arranged to be married. Neither are okay with this.
It is even worse for newly minted Overlord Alastor, who hasn't even been in Hell for very long. Locked in a situation where he is being forced to wed the ex-husband of the woman who holds his leash.
Lucifer can’t figure out why no one else in the hotel is reacting to Alastor flirting with him nonstop.
Meanwhile, he accidentally plays matchmaker.
Through some slightly dubious means and for completely mysterious reasons Alastor turns himself human. In Hell. Unfortunately, Hell has earned its name as a pit of torment for a reason. Thankfully, he has a guardian angel(?) looking over his shoulder.
After a particularly rough dissociative patch, Lucifer’s brain decides to take a vacation and he heads to Earth to play human. Alastor follows to bring him back.
or
Amnesia trope mixed with a bit of human-ish AU mixed with fluff and gore.
Alastor figures out he has a crush on Lucifer. ...Unfortunately, he also figures out at the same time that Lucifer can read minds.
aka
Alastor does everything he can to keep Lucifer from finding out about his crush. Until he changes his mind.
Lucifer was having a bit of a problem. Namely, a deer demon who seems hell bent on getting closer to him no matter what. However, all is not as it seems when signs point to underlying problems.
or
Alastor falls in love(?) at first sight and Lucifer doesn't know how to deal.
Trying to thwart the political machinations of the upper echelons of Hell, Lucifer and Alastor enter into a mutual partnership. The boundaries get blurred over the course of a year as they continually have to work on 'making it work'. Nobody ever said that fake relationships would be easy.
Lucifer wakes up to a life he doesn't recognize. One where Alastor is at his side, his room feels wrong, and something vital in his memory has slipped away. Worse, it somehow feels like Alastor is bracing for something Lucifer can't see coming.