Basically, yesterday, I went to a funeral for the first time in my life, one that was very important in several different ways, because the basic effect from it was an intense desire to live...
...Including the thought that what I'm doing isn't really living. It's sort-of half-living, half-dead, and I intend to fix that, even at the risk of losing everything.
I'll make it up to you with a story idea I had yesterday, though.
This one basically combines the idea of vampires with demons:
Basically, in the setting, Lucifer--like in many of my works--is not in fact evil. He's not exactly a NICE guy, but he's pretty benevolent to those he makes contracts with, and while everything he does is working towards his own personal ends, GENERALLY, it is accomplishing a good thing.
With that in mind, the main character suffers from a lethal car crash, and on the verge of death, Lucifer offers them the chance to live. He (well, he starts as a he, anyway) says he'll accept, under one condition: all the details of the contract are laid out explicitly to him IMMEDIATELY after the contract is made, so he knows exactly what he's getting into.
Lucifer obliges. Basically, the main character is given a ton of supernatural abilities, revolving around hyperfocusing (because he previously lacked a focus in his life, in spite of clear intelligence), and in exchange for it, all he has to do is serve as Lucifer's servant, an 'Enforcer': giving him a purpose in his life that he lacked, and allowing him to help others as he had dreamed.
The abilities that he got are somewhat-standard, somewhat-customized to the individual and their unique contract, so in his case:
-He has near-complete immortality: immune to aging, with immense regenerative capabilities; he CAN die, but it's extremely hard to kill him.
-He can hyper-focus energy into arms and/or legs for immense strength and/or speed.
-He can hyper-focus his mind to instantly solve any task, effectively granting him immense intelligence: this ability is VERY broad, allowing everything from instantly (but temporarily) learning how to cast a fireball to deducing what has happened at a crime scene.
-As an extension of the above, if he uses his hyper-focus ability on the same task enough times, it becomes second-nature, instinctual, and therefore no longer requires hyper-focus to use, allowing him to free up his hyper-focus onto some other thing.
-He can hyper-focus on any of his senses, to the point where his eyes can focus in on the atomic level if needed, see all forms of light, and whatnot, his ears can pick up every form of sound from immense distances, he can feel things on the air to give him a type of 'sixth sense' instinctive defense, he can use his tongue and nose to taste/smell even the smallest things about things, and so on and so forth.
-He has the "Devil's Charm" ability, which basically is amplifying natural charisma with his hyper-focus, allowing for hypnosis of people who see things that they are not supposed to see.
-An extension of the above, he is capable of 'reading' people: by hyper-focusing on them, he can effectively learn their life story, lifestyle, personality, likes, dislikes, and whatnot: everything from their preferred gender to sexual orientation to how open they are to having a relationship, among other things. This ability does have its limits, though; he's not a true mind-reader, and he basically only uses its full power on potential people of interest.
-Even without hyperfocusing, he can tell the nature of supernatural powers he detects that are nearby, allowing him to know what he's dealing with when going in. (He can also tell their origin.)
-This bit is not part of the standard package, but he opted to be given the Devil's Mark on his left forearm: a 6, inverted six, with a 1 separating them. (Yes, inverted 6, not a 9. The devil's funny that way.) This, for yin/yang, allows him to shapeshift, most commonly just into female form. There's a tradeoff, though: it's easily-identifiable, making him a known servant of the devil to any "in the know", and it glows bright red when in use. (It can be covered up, though!)
-Another part of the standard package is blood magic: ritualistic spellcasting using blood, usually his own but also occasionally that of others. This blood magic is a pretty standard ability.
Pretty cool package, and the only cost was his soul: if he somehow DOES manage to get himself killed, his contract will prevent him from being sent to heaven. However, Lucifer explains that Purgatory is actually quite comfortable, ESPECIALLY for his agents--it feels just like life, in fact. It's just that those in heaven have things better than their real-world equivalents, and he won't ever know what that feels like. Lucifer can also take control of him at any time, but that defeats the point of an enforcer: an agent of free will, their main purpose is to do his work and overcome obstacles that servants under his direct orders can't.
And if you're wondering what enforcers do, well, they're basically exactly that: enforcers. If a soul manages to escape hell, it's an enforcer's job to send them back. If someone reneges on their contract, then it's an enforcer's job to call them in. Enforcers serve as messengers for Lucifer, running errands around the world to other servants of his. They also occasionally interfere in the affairs of the world on his command, and are heavily involved in fighting the supernatural entities existing outside the realm of heaven and hell. (Like ghosts and Eldridge abominations.) Plus, they also serve as infiltrators.
They're not on-duty 100% of the time, but are always on-call, the general avatars of Lucifer's will.
There also exists many others who make contracts with the devil, and while most involve the soul, sometimes, there are other things to bargain with. Of these others, a fair number are 'Specialists': people who made a contract (near-universally with their soul), gained some unique advantage, and now with that advantage, live their lives comfortably, until their special powers' services are needed.
As an example, one character is a Specialist whose power is luck manipulation. Most of the time, he is left alone, and he uses this power for effective immortality, gambling, and scoring women. Yet he can occasionally be called upon for two tasks: first off, suicide missions--because he changes luck as a passive ability of his (though he can manipulate it actively with some focus), he's sent into situations where the outcome is supposedly undeniable death, to pull out that miraculous victory. (He is not amused when these come up.)
The other thing? To mess with God. God, basically, has the power to guide the world and see the future, yet with luck manipulation, the specialist's power is strong enough to alter the outcomes such that God--even though he's omniscient--can't see the change he just made.
...In other words, the Specialist's second job? To prank God himself.
He, quite literally, is called upon by Lucifer, to do nothing other than mess with God for the hell of it.
In his own words, "It's a pretty mixed bag. On the one hand, setting the prank up and seeing God's reaction is absolutely hilarious. On the other hand, His retaliation...not so much."
Speaking of God, as Lucifer puts it, "Sometimes, God can be a dick." In other words, God is all-loving, but sometimes He dishes out tough-love and is not amused by the antics of His children. Lucifer was sent to Hell as punishment, but God knew he'd eventually grow to like the job: it'd serve as punishment because he hated it, yet because God is forgiving, He gave the job in the first place because eventually, the perks would make Lucifer be okay with it. That's the type of thing He does with his power--generally, He is a good guy who means the best, but Good Is Not Nice is in effect.
And Lucifer, being the embodiment of free will, holds the power--like humanity--to defy God. Overall, the result of their current dynamic is that while God's path might be the best of the best for everyone as a whole, Lucifer offers a path that is better for singular individuals. Though, Lucifer notes, because God is omniscient, ironically, Lucifer acting out his free will is acting in accordance with His will: God can provoke in Lucifer exactly the reaction He wants from Lucifer should He choose to.
Basically, God is a bit of a Magnificent Bastard: He has the power to see what will be, and influences things for the better, but while His power is great, His power isn't quite such that it's omnipotence. Ever-present, and ever-seeing, He guides things, but even though it causes Him pain, He will sometimes sacrifice the needs/wants/happiness of a few in order to serve the needs/wants/happiness of the many. In short, doing the best He can with what power He has.
Lucifer, though, exists on a different set of rules: he will help whoever he pleases, and often comes to the aid of those that God turns His back on. (Keep in mind, though, that God (1) tries to interfere with humanity's free will as little as He can, and (2) that Heaven being real, He takes them in to relieve their suffering and offer them the happiness they were denied in life.) This can sometimes be an inconvenience to God, but sometimes is what He wants, because if He helped them, things wouldn't go according to His plan, so He tricks Lucifer into it.
In short, an extension of His power is that He tries to help as many as He can, and He needs Lucifer to act in a certain way to achieve that. Sometimes it works, sometimes it doesn't, but the dynamic is there. Lucifer is, loosely, still tied to his "dad", and isn't nearly as strong, but can help God's creation in ways that God can't always do.
For instance, Lucifer making a contract with the main character. The main character being super-powered, God could tell, would do a lot more good than bad, yet if it had been God giving the main character powers, they wouldn't be nearly as strong nor as diverse, because He wouldn't be able to enforce the same amount of influence over the main character. Lucifer might embody free will, yet the contracts he make are contracts that are meant to be followed.
God, in contrast, can no more make a contract than He can with humanity as a whole to worship Him. Obviously, that would be His preference, yet because He allows for free will, He cannot force them to contractually do anything, yet alone, use their powers in a specific manner. (Which is why agents of God are generally Angels rather than humans. Angels have some autonomy, but are not beings born with free will; only fallen angels like Lucifer have gained it.)
Speaking of the main character, though, s/he (later full-on she) uses his/her (later full-on her) powers in her (from now on, I'm using that even though when I described her powers, it was with a male pronoun) off-time to become a private detective: she can basically solve any crime, allowing her to do a fair amount of good and make a fair amount of money, enough to get by on her own.