A/N: Need something a lighter than 'Beyond and more', well, lighter is relatively suggestive here considering the premise.
First thing first, this fic is actually a crossover with an indie game called Helltaker, but don't worry you don't need to play the game to read the fic. Though the game is free, so maybe give it a try. It is a puzzle (with some bullet hell) game on Steam where you play as the guy trying to get a harem of demon ladies. You all probably like it, go give it a go. As I said, it's free after all.
Oh and don't you worry, there's a lot more to Hell than in that game… *ahem* Hazbin Hotel and Doom *ahem*.
Beta by Yuilhan
Izuku's head hit his pillow hard. He was tired beyond belief.
Today marked the end of his first week at middle school, or as he would like to call it 'Hell on Earth'. Everyone usually looked down on him being Quirkless, he'd been used to that for a long time, but now it had started to get out of hand; probably had something to do with Katsuki's 'encouragement' of his bullying.
For now, it was just constant jeering and insulting, but he knew it wouldn't be long before it would get worse.
Sometimes he wondered if Hell was better than here. At the thought the boy chuckled; maybe it might be better. At least the demons down there tortured you all equally; he would end up in as much pain as the next sinner. And hey, there might even be gorgeous demon ladies like in one of those games or animes.
Izuku kept entertaining his dark humor for a while before slipping into a deep slumber for good. Unknown to him, however, his fate was about to change. Especially when a pentagram appeared underneath him and flashed brightly with crimson light.
When the light subsided, Izuku was gone.
He was in for a Hell of a ride.
Izuku slowly opened his eyes.
'Why is the bed so hard? And why is it so hot? Did the air conditioner bust?'
Izuku got up and soon realized he wasn't in his room anymore. He was in some kind of canyon. Judging from the tanned orange color of the rock, the greenette at first thought he'd teleported to the Grand Canyon, but then he looked up at the sky. There was a ceiling, a very large and high ceiling, and black clouds as if they were created from smoke swirling above.
"Wha-where am I?!" Izuku shouted.
"Ah, you're finally awake!" someone said, with an echoing effect.
Izuku turned to face his no-doubt kidnapper. He was greeted by a tall muscular man in a suit and a button-up shirt, the topmost button undone. His visage was hardened with a strong chin and jawline, but his eyes were hidden behind sunglasses… and he looked... strangely familiar… wait.
"G-Great-granduncle!?" Izuku shouted as he recognized who this was. The greenette had seen this man many times in the old family photos his mother kept.
"Glad you recognized me, great-grandnephew," Izuku's great-granduncle said with a small smirk, but it quickly disappeared. "Right, I will get to explaining, since I don't have much time left. I have already completed the ritual after all."
"R-ritual w-what ar-are yo-" That was when Izuku noticed something about his great-granduncle; his form was ethereal and blue. "Y-y-y-y-y-you are a ghost!"
"Yup, like I said I will start explaining." The ghost cleared his throat, though Izuku was baffled by why he still needed to do that. "Do you remember how I just up and disappeared one day?"
"Y-yes. Grandma told us that story every time we visited her." Izuku suddenly looked sad. "She already passed away though."
"Huh." His great-granduncle scratched the back of his head while looking somewhat remorseful. "Guess I missed a lot about you guys, huh? Still, I know what I signed up for when I left. On that subject, the reason I left was…" Izuku leaned in with anticipation. The disappearance of his Great Granduncle had always been a subject of debate and speculation within his family, and now he was about to hear the reason behind it. "I left for Hell in order to gather a harem of demon girls."
Izuku had to do quadruple-takes before finally recovering. Even then he still stared, wide-eyed at the ghost as if he was a madman, or 'mad undead'. Now Izuku had begun to feel like this was all a dream, a really, really strange dream. That was until the ghost extended his hand forward and pinched him, hard, on the arm.
"Just to make sure you know this wasn't a dream. The thing about my quest is, I failed," the ghost revealed. "There were many traps, foes, and puzzles in Hell — not to say the very demon girls I am trying to get into my harem can be less than hospitable."
"A-and how far did you go?" Izuku questioned before looking around. He saw a giant metal double-gate entry with the letters 'Welcome to Hell' above it along with a front door mat which was comically small for a door that size.
The greennette gave his ancestor a dead stare. "...you failed at the entrance, didn't you?"
His great-granduncle averted his eyes from Izuku's. "...well in any event. I need your help. You see, I am about to disappear since my time limit is up."
"Yes, Hell isn't exactly… a friendly environment for a wayward spirit," the great-granduncle explained. That's when it hit Izuku where he was.
"OH. MY. GOD. I am in Hell!" Izuku screamed at the top of his lungs. He knew his last thought was about a bunch of demon girls but he didn't want to end up here.
"Yup, I summoned you here to get a harem of demon girls in my place."
"Yeah, yeah, cry me a river, it's already done, a one-way trip down under. Sorry for the dickish move, great-grandnephew, but I need to make sure you will go all out and get that harem that I couldn't and then get out of this place; tonight we dine in Hell and all that."
"BUT WE ARE ALREADY IN HELL!" (Izuku never knew he could be this loud.)
"I know, I know, but I am not leaving you to the wolves though. I will let you inherit my Quirk through spirit transference before sending you on the way. Two Quirks should make a difference, yours and mine." Izuku grimaced at that.
"I-I am Quirkless, great-granduncle," Izuku admitted, his eyes downcast in shame.
"Meh, not like that's a game-changer," the great-granduncle said casually, much to Izuku's surprise.
"You… you don't care that I am Quirkless?"
His great-granduncle frowned. "Two things, kid: first, Quirkless doesn't mean powerless, you can still kick several peoples asses if you train yourself well. Secondly, we are family; we stick with each other regardless." The ghost rested his hand on Izuku's shoulder, but his form soon started to flicker and fade. "Right, my Quirk is called 'Hell Legs'. It will enchant your entire legs, which include knee caps and feet, basically all of it, to the point that you can kick anything up to around three tons with ease — and that's without training! It can also create flame around your feet, but that's kind of useless in Hell." At this point, the legs and arms of the ghost were already fading out of existence.
"W-what will happen to you?" Izuku asked.
"Probably get reincarnated, preferably in another world but I can't choose that." The great-granduncle placed his knuckles over Izuku's chest, where his heart ought to be. "Go get a harem of demon girls for me, kid."
"I-I will," Izuku sniffed. The boy might not have known his great-granduncle well, and his great-granduncle might not think much of this, but for Izuku to be able to have a Quirk was more than he could have ever asked for. Besides, as the ghost said, family is family, regardless of their abilities; they would weep for each other.
The great-granduncle smiled. "Go on, kid. Go fulfill my dream for me, become the Helltaker in my place." With his parting words said, he disappeared. Only a wisp of red light remained in his place. It immediately flew forward and struck Izuku in the chest. The boy felt a surge of energy in his heart which spread through his entire body before stuttering out.
Izuku was shaking afterwards, but he quickly forced himself to stop. 'Okay, take a deep breath, a deep breath.' After doing that he eventually calmed down. 'Right, I am still not sure if this is a dream, but I'd better take this seriously in case it isn't.'
The boy began to observe his new surroundings. He was actually standing in the middle of a blue line drawn in a circle. Considering that nothing harmful had come his way so far despite being in Hell, he would wager that the circle worked as some kind of protective ward, and he should really think really hard before stepping out of the circle. He also found a set of clothes and circular sunglasses on a coffee table made of stone and a paper strapped onto it.
'A few heads-up, since I didn't know what kind of state you would be in when I summoned you, I have prepared this clothing for you. What is next is more vital, Hell's environment is, well, Hellish. Us mortals wouldn't survive for long, but some good news is that when you enter the next level of Hell there seems to be a recharge of your spiritual energy; you have limited time and moves in which to make it from point A to point B, so consider all your actions wisely. None of this can happen while you are in the protective ward I drew though.' Izuku paused his reading to breathe a sigh of relief.
'Still, you'd better get going. Now that I am gone, even my ward will start to deteriorate soon, and I hope you drank water beforehand because it's hot as Hell down here.' Izuku gave a dry chuckle at the pun. 'Good luck great-grandnephew, or great-grandniece… I am sorry, but I only knew that the person I am summoning would be my relative down the line and that's it. I wish you luck. P.S. I want to get you the white and red ones, but in Hell there's only the black one and they ran out of the red one as well. Sorry.'
Izuku became confused at the last bit. Was his great-granduncle talking about the clothes he gave him? Izuku unfolded the clothing and observed it. It was a black suit with a dark green dress shirt, and some black, straight cut pants. Beneath the pile of clothing were a pair mens black leather shoes to go with the suit.
The greenette changed into his new clothes, because he was sure as hell not going through Hell in his pajamas. He kept all the buttons on his shirt buttoned though, unlike his great-granduncle; he was a good boy like that. Once he was done, he looked quite neat, and frankly, the clothing change made him feel a little more ready for the task ahead.
After all, he was going to convince the demon girls to join his harem… another realization quickly hit Izuku.
"OH GOD, I'VE NEVER TALKED TO A GIRL BEFORE!" Izuku yelled out loud, unable to contain the thought within his head.
This was not looking good for him. How would he even talk to a girl, much less a demon girl?! The boy began hyperventilating at the thought. That was when he saw the circle's lines begin to flicker. The greenette immediately ceased his panicking and thought of his more pressing issue; his new Quirk.
'Right, great-granduncle said his Quirk works through his legs, so let's try this. Now should I use it?'
As Izuku began to focus on his legs, things seemed to come naturally to the boy—as if this was his Quirk he'd had for all his life. Soon he felt his leg heating; giving his new Quirk a try, Izuku trialed kicking a nearby pillar of rock. His kick easily broke the pillar away from the ground and sent it flying into the wall, shattering it to bits. He took a deep breath and the legs cooled down.
"Thank you great-granduncle," Izuku muttered, grateful for this gift. He would have cried tears of joy right there and then if it were not for the fact that he had to get out of here first so he could use this gift to its fullest.
After testing out a few more kicks, including taking off his shoes to see if flames could emit from his feet, the greenette believed he was ready; and just in time too. The circle began to flicker more and more. It would fade soon.
So with one last deep breath, Izuku ran out of the circle and descended down into the canyon of Hell. As soon as he left the circle line, he could feel the true oppressive atmosphere that was the Torture Pit of the Damned. He felt like fainting, vomiting, collapsing, dying. Still, he pressed on despite his laborious breathing; this was nothing compared to just dying and suffering an eternity of torment.
Eventually, he encountered his first obstacle; a 'muscular' construct made out of bones roughly the size of an American football player, with a pair of horns as well. It spotted him and immediately took a stance like a basketball player ready to block.
Izuku was afraid, but also undeterred; he couldn't afford to hesitate with his life on the line. Yet, he knew he must dispatch this foe while expending as little energy as possible and as quickly as he could. Thinking back to the pillar, Izuku found a good way to deal with it. Imitating the clips of Pro-Heroes he had watched and analyzed so much, Izuku made a well-placed kick to the side of the skeleton and sent it crashing into the wall. The result was as expected, it broke down into bone fragments.
The greenette couldn't help but smile. He had a Quirk and a good one at that. If this was indeed a dream, he really didn't want to wake up… but if it really wasn't a dream then he needed to focus. Izuku continued on, avoiding the other skeletons since they were neither in his way nor pursuing him.
That was until he encountered a new type of obstacle; a giant square block of motherfucking rock. There were several of them, in fact, completely blocking his path forward.
'Dammit, I have to destroy them somehow… or move them.' Izuku looked around trying to see if there was any room to kick these rocks out of the way. They shouldn't weigh more than two tons, which was within his limit, according to his great-granduncle. That was when he spotted it, a craving on the wall, displaying the layout of the entire canyon including the skeleton placement and the space between the stone where he could push the rock toward to clear the passage.
Izuku was quite baffled at this, and thought about whether this was a prank by the denizens of Hell or something, but as he felt more and more exhausted despite standing still, he knew he didn't have much of a choice. He analyzed the layout and quickly came up with a solution to solve this puzzle.
He ran to the boulder on the right of the passage and took a deep breath.
'Alright "Hell Legs", don't fail me now,' Izuku prayed in his mind before using his feet to shove the stone forward, and it moved. It was pushed across the ground and only stopped once it hit with another block of rock, or at least it should be another block if the map was correct. 'YES! Thank you, Hell Legs!' If his Quirk was sentient, it would blush… 
With that, Izuku quickly solved the rest of the puzzle and continued on. He felt more drained as he journeyed onwards. The contents of his stomach kept rising and falling, urging him to vomit them out, but he knew that if he stopped he might end up dead for good. Eventually, his vision fixated on the metal gates a short distance away from him. The greenette dashed towards it.
In the presence of the gates, Izuku felt re-energized and no longer on the verge of death. His back leaned against the frame of the large door and took a few deep breaths.
Midoriya closed his eyes and shot his arms up in the air, both to help with the breathing and to celebrate. 'I did it, great-granduncle; I survived.' Izuku thought with joy; now he had some hope that he would return to the living world.
That was when a shadow fell over him. The boy slowly opened his eyes to discover… a demon girl.
How could he tell that she was a demon girl his great-granduncle had told him about? Well, if the short black horn on top of her curly pony-tailed hair, her pale, light-greyish skin, her tired red eyes behind a circular glasses, or the thin arrow-tipped tail that came out from under her black thigh-length business skirt didn't make it obvious enough, her employee card, which connected to her neck strap, clearly display the word 'Employee of Hell'.
The demoness stood over Izuku, observing him with her cold piercing gaze. Then, she took her eyes off him to look at the paper on her clipboard.
"Strange, the memo didn't say there will be any souls coming in through this route today," the demon girl said as she flipped through her paper before sighing. "Oh well, it can't be helped." She cleared her throat. "My name is Pandemonica, I'm Hell's Customer Service helper," the demoness in black and red business suit introduced. "How may I serve you?" 
Izuku immediately got up and began to panic, flailing his arms around. If there was one thing he considered to be harder than running around and solving puzzles through Hell, it was flirting with a girl—no, this demoness is definitely a woman. Gosh! Flirting with someone older made him even more nervous than flirting with someone his age did.
He had to come up with something, a cheesy pick-up line, a genuine compliment, a flirtatious statement, or just anything, to say to her. Dammit, being a social outcast because of your Quirk status really put you at a disadvantage, he supposed.
"UH, UM, UH, UM, UH, I REALLY… LIke… your…" The greenette trailed off. As he observed the petite demon girl, he began to notice that she looked extremely tired. The bag under her eyes was even more noticeable than his mother after a sleepless night and her eyes just screamed 'dead on the inside.' "You looked really tired, are you alright?" the boy asked, genuinely concerned, and forgot about the whole flirting thing entirely.
Pandemonica sighed and yawned at the same time. "Honestly, no. I have been doing this job for a few days without my coffee," the demoness informed, adjusting her glasses. "I'm just not the same without it." She dropped her stern posture and hunched down like an exhausted office worker at the end of the week.
"Oh, that's terrible. Is there a way I could help? I could go make you some while you're doing your job here," Izuku offered.
The petite demoness blinked in surprise. "That's sweet of you to offer, but I don't think you… wait… are you… alive?" Pandemonica narrowed her eyes at the boy. "You shouldn't be here, only the damned should."
"W-well, you see here's the story." Izuku then began explaining how his great-granduncle summoned him here to fulfill the late man's wish of having a harem of demon girls.
"I see, that would explain why you aren't on the list." She readjusted her glasses as she looked over her papers once more. "The rules are the rules, though, once you are in Hell, you aren't leaving."
Izuku sucked in a deep breath. "That's fine. I will get out of here." He supposed desperation was a great fuel for determination. "But do you still want me to do anything for you before I leave? Like I said, I could run out to get you a coffee real quick then be on my way." Honestly, he wouldn't mind going out without a harem, even if it would greatly disappoint his great-granduncle, he would rather leave here alive.
There was a short silence from Pandemonica. "Actually, I think I will be joining you."
Izuku had to do the double-takes. "Excuse me, whatttttt?"
"I said I will be joining your harem and your adventure through Hell," the demoness said, the corners of her lips slightly pointed upward. "Honestly, I could use a break, and if you succeed, well, it will just become a vacation instead. Beside… you're offering me wake-up coffee." Pandemonica shrugged her eyebrows suggestively at Izuku.
Izuku quickly realized that she meant he was offering her a wake-up coffee in the morning... the morning after they'd spent the night together. The greenette's face turned red enough to match the color of the demoness' eyes.
"Wha-wha-wha, wwelwellwelllwelwle." His speech was barely comprehensible at this point. "I-I-I-I-I-I-I AM GALD TO HAVE YOU IN MY-MY-MY-"
"I suppose it would be fun breaking my routine a little. So, shall we get going?"
Izuku swallowed audibly. 'Come on Izuku, you finally have a girl accepting your advances… or you in general. Get your shit together!' He took a deep breath and offered her his arm.
She took his offering and locked their arms together, resting her hand in the crook of his elbow. "A little old-fashioned, but I do appreciate a gentleman. Say, what's your name?"
"Oh, I'm Midoriya Izuku, umm, I mean Izuku Midoriya, sorry."
"That's fine, we demons can understand any language," Pandemonica informed.
Then a name suddenly popped up in Izuku's mind; the title his great-granduncle hoped he would inherit. "Though if you want, you can also call me… Helltaker."
"Hmm, well, you are here to take demoness' like myself away from Hell, so I suppose it is fitting," Pandemonica mused.
And so they walked arm in arm through the gate together. Izuku had acquired the first member of his harem, a new path in his life had been set, and Pandemonica would get her coffee. Eventually.
A/N: And that's how Izuku is going to win them over, being the genuinely caring cinnamon roll he was.
 Admit it, some of you failed a few of the puzzles like I did and have to look up a guide.
 No legs in the harem.
 I imagine Pandemonica's voice to be similar to Dandy from OK. KO. (Melissa Fahn is the voice actress in Eng. ver.). But you can just imagine her voice however you want.