A Whole New Demon Slayer(s)

 Fifteen years ago, the entire world was shaken when mysterious gates opened, and all manners of creatures emerged wreaking havoc. Modern weapons had little to no effect on these beings, their devastating attacks claimed many lives. However, a mysterious energy that would be known as "mana" appeared after the gates started to open. It caused humans to begin to awaken various abilities of their own. Armed with these new powers humanity's counterattack began, now awakened warriors known as hunters take on these dungeons to clear them before the enemies from the other side can come through. Hunting has become one of the most noble professions globally, with many hunter's unions known as guilds forming to organize the hunter society. These groups compete to recruit the best talents to clear more dungeons than the other guilds. The promise of riches has also brought in many warriors who are paid large sums for successfully closing dungeons. It helps that the items and materials harvested in dungeons have high quality and rare properties, but most importantly can be made into powerful weapons to use against the otherworldly invaders.

 As more and more people awaken at random a myriad of abilities appear ranging from enhanced physiques, magic, aura and so much more. And as random as the rest of one's awakening is the amount of mana one can awaken, directly affecting the scale of their power. Some became like gods amongst men. These high rankers are looked upon to heroically lead the charge in dungeons, but some would rather use their newfound abilities for less than honorable purposes. Superpowered criminals have become a new threat to society along with the hordes of monsters. Along with the guilds, new criminal groups have formed called dark guilds. The threat of monsters in human skin was answered by the dark guild hunters, who work to combat these groups wherever they arise. 

As modern society's focus shifts to the world of monsters and the awakened, there are many who remain powerless and unable to fend off even the weakest of monsters. No awakening means no need to enter the dangerous dungeons, a task best left for the hunters. Even still, not everyone is content to continue living a boring mundane existence, knowing the life of a hunter is a possibility. For those who dream of slaying monsters in dungeons, easily amassing wealth, or attaining the fame of a modern hero they can only hope and wait for fortune to smile on them. There is no guarantee of them ever awakening in their life, nor any known means to force it to happen either.

 Among those who refuse to face the harsh truth of being forever unawakened is Oliver King, who devoted his entire life to hunting as soon as it became an option. Yet fifteen years later the hopeful nerd is now a tech industry executive who would rather die than spend the rest of his life behind a desk. He hoped and waited… but no powers. Every move he made was in preparation for the day he awakened; extensive physical training, deep studies on all things related to these dungeons, amassing of wealth and weapons…but still no powers. The weakest of monsters is still a struggle for him to survive against, let alone defeat them. Has his whole life been in vain?

 "You shouldn't worry about going into dungeons so much, just focus on your business outside the gates until you awaken. Even if you never awaken, I'll always be here to protect you."

 "Yes…that's exactly what I want to hear from my girlfriend who lucked into an S rank awakening and became a top ranked huntress in the United States. Am I happy for her? Of course! I helped her train and discovered the extent of her abilities. Am I jealous? Definitely! We should be fighting side by side, but I'm stuck on the sidelines trying not to die! If that wasn't infuriating enough the ingrates who work for me are trying to take my company from under my nose… I'm over all this, it's all too stressful…maybe I'll go away for a bit…"

 Having ended up back in his small rural hometown, Oliver decides to visit a dear old friend who he knows he can always lean on. All of this will seem like a trivial melodrama to a person who is actually glad to stay out of the dungeons. Hank Mays, the only member of his old friend group who never left town and has even been running a local metal shop. Hank is a dependable guy, grounded and straightforward. A friend like that would be really helpful to talk to right now.

 "What?! You've thinking about selling the shop? You never awakened, and it turns out you need to have mana yourself to refine the magical tools? All but one of your employees quit and joined the hunter society headquarters? People aren't even buying your products anymore because magic tools are all the rage now. How can you say that craftsmanship can't compete with magic!?! What kind of nonsense is that!?! What a cruel world, not only did it step on my dreams, but it ruined my best friend's craft too! Seems like he's going to have to find a new career path soon, and he really loves his job. Not to mention he is one of the best smiths I've ever seen, his work even compares to historical masterpieces. Don't tell me I'm being dramatic!"

 If Hank's woes weren't plenty enough already, he has the misfortune of having none other than Oliver's own older brother as a guest for an unspecified amount of time. The arrogant, snobbish, snarky, Benjamin King exclaimed "I won't be caught dead in this shithole of a town ever again," when he left his wife and daughter (he got kicked out) years ago to pursue his career as a doctor in New York. Apparently he was much better at medicine than taking care of his family since he earned quite a reputation among high profile clientele and made good money, even with healers starting to take the place of surgeons.

 "Recently, Benjamin's life recently took a drastic turn when a hard decision had to be made, and someone with a lot of sway lost their life. After getting blacklisted he can hardly find work as a school nurse, working under the operating lights again is completely off the table. He put up a fight but ultimately life beat Benjamin too. Hence the sad excuse of a man rotting away at the bottom of a bottle. He doesn't even have the gall to face his own family… it's nowhere near as satisfying as I thought it would be to watch. This isn't the douchebag I once aspired to be like. It hardly seems worth it to fight him about it anymore."

 "Just when I thought this pity party couldn't get any worse, the fourth and final member of the old gang, Leonardo Masters, arrives. You guessed it, not only did he not awaken but life kicked his ass too, and he needed a place to crash. His endeavor (endeavors actually) as an entrepreneur have given him opportunities all over the world yet they always blow up in his face. He's resourceful, innovative, and a quick learner, traits that should've taken him pretty far. On the other hand, he only thinks he's heartless and crafty enough for the dark side of the business world. Getting ripped off or fucked over is kind of his regular routine at this point."

 "Wow… who would have thought we'd all crap out so young. This is pretty sad, so much time and potential wasted. I mean it's not too late to start over, but what now? Start a band? Become Firefighters? Pro wrestlers? Open a night club? Nothing sounds good when the perfect life was just at my fingertips… You know what? Let's not dwell on these nightmares. We just need some time to reflect and adjust. I'm sure it'll all work out."

 "On the other hand, it's been years since the four of us have all been in one place. In a sense that's a call for celebration, when the chips are down who better to have your back than your boys? Wait Hank kept the old van we all chipped in for years ago? Why don't we all take a road trip! Hit the open road, have some fun, make a few new memories and then we'll figure this mess of our lives out. A perfect plan…except we didn't get very far until we remembered why we didn't really keep in touch, these guys are insufferable! We argued until we swerved and hit that tree…"

 "Ding! Multiversal anime travel system activated!" We all woke up on a random lush green hill, completely unharmed. There wasn't even a scratch on the van, but somehow the old navigation system (that stopped working a long time ago) is on and talking to us. "This van allows for travel to different anime universes where passengers will live a life to complete an assigned mission. All skills, abilities, and items acquired will return with passenger to the real world upon completion of mission. Upon completion of missions, merit points will also be distributed. Merit points can be used in system shop to acquire items and abilities. Merit points are earned from passenger's contribution to mission's success."

Warning! Upon death in another universe passenger must wait in van until remainder of mission and complete remedial mission.

Warning! Dying in remedial mission results in permanent death 

Warning! Van can only travel if all four passengers are present 

 Do you accept? 1/4, 2/4, 3/4, 4/4 

 First stop: Demon slayer

 Mission: Kill Muzan Kibutsuji

 "This is a golden opportunity to fix all of our problems…Wait what's an anime?"