"It hurts."

At that, everyone present could only turn towards a jacketless Mikazuki, who was staring at his regular arm with a somewhat confused expression.

Husk was quick to lower his flask and glance in Mika's general direction from his spot in the hotel room while Niffty stopped patching up the hole in his jacket, with her single eye now glued onto the pilot, who kept his gaze on his flesh and blood for Alastor, he simply eyed Mika from where he sat, tearing his gaze away from his book.

As usual, the Radio Demon's smile was still present, something that made him nearly unreadable, with the only indication of his curiosity being his mildly raised brow.

"Mr Mikazuki?" muttered Niffty as she placed his jacket off to the side and moved to the pilot's side. As she did, Augus glanced in her general direction with a raised brow, surprised at the genuinely worried expression Niffty had. Hard to believe that she was a demon, honestly, though he dismissed that thought as another wave of pain surged through his regular arm. "Is something wrong?"

"My arm. It hurts," muttered Mika, the fingers of his regular arm twitching a little as he spoke. At that, Niffty tilted her head a little off to the side before she moved to place a hand atop his regular arm, and that gesture was enough to make Mika's lip twitch in apparent pain, though he didn't show any signs of it outside of that.

Hell, Niffty didn't even acknowledge it. The only thing she did acknowledge, however, was how… cold the limb felt. Almost as though it were dead. Sure, this was Hell, but demons still radiated heat. They radiated, for the lack of a better term, life.

And Mika's arm sure as Hell wasn't radiating either at the moment.

Perhaps this had something to do with his last task from Alastor? He did tell him to fight some sorta ice demon working under that Overlord, Velvet, didn't he? If so, perhaps… no, that couldn't be right. He fought and killed that demon yesterday! And she remembered his arm being warm, even after he had melted ice that was over three inches thick off it!

So that left only one option…

"Oh no…" muttered the cyclops demon as she looked Mika in the eye. In response, Mika simply raised his brow in confusion, unsure of what to make of those two words as Husk grumbled about losing his queen card from over at his corner of the room. Meanwhile, Alastor's ears perked up at the sound of that, and his smile grew wider as a result.

"Hm?" replied Mika, his gaze fixed on the cyclops, who seemed rather worried about speaking of what was happening to his arm, though Augus was a patient fellow, as evident by how he simply waited silently for an answer.

And as luck would have it, before Mika could run out of patience, he felt a hand rest atop the shoulderpad of his Lupus Rex arm, prompting him to glance towards whoever had done that and raise his brow when he made eye contact with Alastor. The faint sound of static was apparent as the Radio Demon glanced down at him, with his smile unsurprisingly maintained as he chuckled briefly.

"Don't be such a ruffian, Mikazuki Augus! Niffty is clearly uncomfortable with speaking the truth! And Hell, why reveal it so quickly?! It would ruin the surprise!" scolded Alastor, leaning down until his face was right next to Mika's as he spoke. Mika frowned as he moved away the Radio Demon as Niffty blinked a little, though she remained silent as the Overlord chuckled and adjusted his monocle. "Though seeing as how I consider myself to be a gentleman with some standards, I will give you some advice…"

And at that, the Radio Demon's tone darkened, with his smile growing so wide that it could split his face in half if it were to increase in size. It was enough to make Augus get somewhat defensive, though he did still hear what the Radio Demon had to say.

"Be prepared…"

And admittedly, Mika did feel a chill go up his spine as he processed those words. Glancing at his arm, Mika frowned as he clenched and unclenched it gently, feeling a small amount of pain surge through it as he did.

But that was all it was, right? Pain would eventually come to pass, and he'd be stronger for it… right?

Pain… so much pain…

His arm, from his shoulder down to the tips of his fingers, felt as though it had been dipped in lava. It had started as a mild pain at first, but as the days went by, that pain only intensified., Augus had assumed that he could weather the pain… though by now, it had gotten so bad that he found himself unable to move his limb, with every twitch of his arm causing him immense pain.

Hell, it had gotten so bad that he was unable to even move that arm, essentially crippling him as both Alastor's hired help and Barbatos' long distance hitman until the pain subsided, though thankfully the former didn't mind as he saw Mikazuki's agony as entertainment in of itself. As for the latter, he was not informed of any of this.

Niffty was surprisingly worried for the pilot's wellbeing, especially for a demon. The little cyclops stayed by his side at all times, typically offering her help whenever possible. Mika did feel rather grateful for her help, though he wasn't able to show it properly due to the pain in his arm. Granted, the guy probably wouldn't be able to show it properly even without the pain.

Husk, on the other hand… was still Husk. Drunk, rather uninterested in the pilot's whole ordeal and usually passed out, as per usual, though according to Niffty, the cat demon did (somewhat begrudgingly) provide Mika some help with the jobs he had been issued by Barbatos whilst he was out of commission, at one point returning half drunk and somewhat injured, though Niffty had mentioned that it would be fine as long as he got his share of his payment after Augus' arm was better.

The pain had lasted… more or less for three days, with the pain intensifying tenfold with each passing day, though the pilot had refused to show any actual pain outside of the occasional grimace.

And yet… at the end of the third day, when the skin on his arm began splitting, he couldn't keep it in.

The pilot vaguely remembered how it happened, with him just sitting on the bed of the hotel room, Alastor by the side, reading his book while Niffty offered him a cup of what was hopefully water. He was still unused to being coddled in such a way, though he still accepted it from Niffty, who smiled as he took it with his Lupus Rex arm.

And yet, the moment she had released the cup, Mika widened his eyes as a massive amount of pain began surging through his regular flesh and blood arm. It was enough to make him grimace a little at first, though the moment that cup had crashed against the ground, enough pain surged through his arm to make the pilot lose his cool demeanor.

His mild groans became a loud chorus of pained wailing within seconds, and Niffty couldn't help but gasp as she leaned forward to check on her colleague. However, before she could, Alastor snapped his fingers and within a second, the cyclops was teleported in front of him and away from Augus, who had fallen onto his side by then.

"Now now, Niffty. You and I both know that this is standard for whenever this happens. Just leave little Augus be for now. After all, you could be unintentionally hurt by him if you get too close," suggested Alastor, smiling as he patted Niffty over the head. And while she did obey the command of her boss, the little demon couldn't help but feel just a little guilty as she watched Mika grab his regular arm with his Lupus Rex limb, crying out in pain as the sound of skin tearing and flesh ripping apart could be heard.

Several hours had passed before the sound of skin and flesh tearing apart subsided, and by then, Husk had returned from god knows where.

When he had entered the hotel room Alastor had booked out, however, the cat demon wasn't exactly prepared to see Mikazuki lying unconscious in a pool of his own blood in the middle of the damn place, much less how Niffty was actually ignoring the blood that dirtied the ground, with her attention being on Mika.

"What the fuck happened here?" grumbled Husk, rubbing the bridge of his nose as he shut the hotel door, his face buried in his free hand with his fingers spread apart just enough for him to glare at Alastor through them. "Oi, Radio cunt. Mind spilling the beans? Didja get hungry and decide to eat the fucker?"

"I could explain, or you could see for yourself," suggested Alastor, not looking away from his book as he spoke, though his tone did have hints of sarcasm, most likely in response to the bold claim of him having eaten Mika's arm. Husk didn't like the sound of that, though he nodded as he approached Mika, with Niffty glancing up at him as he did.

"So, uh, mind tellin' me…" muttered Husk, only to trail off when he noticed that something about Mika was off.

Specifically… it was how the pilot's left arm looked…

"... what the fuck is this?" muttered Husk, frowning as he crouched down to look at Mika's new left arm in shock. His response was nothing more than silence from Niffty and a mild chuckle from Alastor, something that didn't bode well with him. "Hey, I asked a fuckin' question! Mind giving me an answer?!"

"Ah, well you see, Husker ol' pal," began Alastor, smiling as Husk glared at the Radio Demon, an unsavoury frown on his lips as he listened.

"Mikazuki is simply growing up!"

Mika had woken up roughly a day after his arm had undergone its… transformation, so to speak.

The moment his eyes cracked open, the pilot immediately realized that something was wrong, though that in itself wasn't hard to notice when he saw that Husk, of all demons, appeared worried about him. Niffty too appeared rather relieved that he had woken up as well, though Alastor didn't seem to care. Figures, Mika reckoned, considering how he was nothing more than entertainment to the Radio Demon.

"Ah, you're awake, Mikazuki," greeted Alastor as Augus sat upright, frowning as he shook his head. As he did, Niffty blinked her eye and immediately leapt onto the pilot's chest.

"Mr Mikazuki, are you feeling alright?! When your arm exploded I thought you were done for, but it was just natural growth and all that! But even so, you lost a shitton of blood! And your new arm looks cool! What is it based on? Could you-" rambled Niffty, confusing Mika to no end as he simply glanced at the little cyclops, with his head aching a little as he listened. After some time, however, Husk apparently took pity on him as he grabbed Niffty by the collar of her shirt and lifted her off Mika's chest.

"Hey now, the fucker just woke up. Leave em the fuck alone," grumbled Husk, not sounding drunk for once as he glared at Niffty in his hand. The cyclops seemed to understand as she nodded a little apologetically, and at that, Husk sighed. "But regardless, you feelin' peachy? That new arm feeling alright? Sure, you're a proper bastard but you're good at keeping the casino fuckers away from me, and with one arm outta commission you'd do a worse job than you usually do!"

And at that, Mika simply raised his regular hand up to his head and rubbed it in confusion…

… only to pause briefly when he realized how… cold it felt when it made contact with the side of his head.

"...what…?" muttered the pilot as he glanced at his left arm, only to widen his eyes when he saw what it looked like.

Instead of the rough, sunbaked skin he was used to, Mikazuki's arm was, for the lack of a better term, the arm of the Barbatos Form 1. His actual arm was now the inner frame of Barbatos, pre-Lupus upgrade, and the outer armor was that of its first form, with the pure white upper and lower arm armour. Unlike his Lupus Rex arm, his new left arm had no shoulderpad, with just the inner frame skeleton hanging off it, and the most noteworthy thing was the light blue gauntlet that rested on the outer side of the forearm armour, and as of now, it was so shiny that Mika could see his own reflection on it.

For a moment, Mika simply eyed his new left arm, his expression unreadable as he did so, with Husk and Niffty both looking somewhat curious as to how he'd react to it after the initial shock had worn off. Hell, even Alastor was glancing in his general direction with an expecting smirk.

That smirk did admittedly falter a little when Mika simply snorted, however.

"Hm," muttered Augus, clenching and unclenching his new left hand, with the sound of metal gently shifting against metal somewhat audible as he glanced at it. He gently tapped his Lupus Rex claws against the gauntlet, noting how durable it sounded as he did so, probably able to tank a minor magical attack if needed. "Neat."

And to that, the Radio Demon couldn't help but let out a slightly disappointed chuckle.

"Well, that was anticlimactic," quipt Alastor as he took a sip from his cup of questionable liquid, though Mika ignored his comment as he kept his gaze on his new arm.

"How did this happen?" asked Mika, still ignoring Alastor as he clenched his new left hand into a fist, feeling rather surprised at how natural it felt to move his new mechanical limb, though then again, his Lupus Rex arm moved just as well as his old one, so he supposed that this was to be expected…

"Well, you see, you lil fuck. When, uh… when you first come down to Hell and all that…" muttered Husk, rubbing his chin with his claws as he tried to put whatever he wished to say into words. Niffty herself also seemed somewhat unsure of what to say, though thankfully enough, Mika was patient, and as such, he silently waited for an answer.

… one that came from an unlikely source.

"If I may?" came the vaguely familiar voice of Alastor's sentient microphone cane. Even Alastor appeared somewhat surprised that his cane had spoken up so abruptly, though he didn't see any reason to stop it as he held it up, allowing Augus to hear it better. "Ah, thank you my good chap!"

Alastor chuckled in response, with the microphone speaking up as soon as his chuckle ended.

"Now, settle down little pilot, for I shall be telling you of Demonology 101! Or more specifically, Sinner Biology 101!" continued the microphone, with Augus raising his brow as he anticipated the microphone's explanation. "Allow me to be brief, When a Sinner first arrives in Hell, their physical appearance will not be altered too intensely. A small change here, a new eye there, all that creamy stuff! However, the more powerful a Sinner grows, or if they grow older, their physical appearance will be altered, inevitably turning them into a demonic shadow of themselves!"

And at that, Mika couldn't help but glance at Husk and Niffty with raised brows, silently wondering what they looked like prior to all this. The two seemed to notice his gaze, however, as the cat demon rolled his eyes and crossed his arms.

"I had a bitchin beard, just so you know," quipt Husk rather sarcastically, puffing his chest out in a rather proud way whilst Niffty chuckled.

"I think I was a little taller," added Niffty, holding both hands behind her back as she nodded. "I… don't exactly remember, though. It's been… how long has it been…? I forgot."

"Well bein' down ere' in Hell does make your memory fuzzy, that much I can confirm!" proclaimed the microphone, with Alastor rolled his eyes as he chuckled, half agreeing with that statement as the sentient cane continued speaking. "But back on point, the longer you remain in Hell without dying, the more powerful you will become, and as a result, your body will change to suit your more powerful state!

"These changes usually begin between three months to a year after arrival in Hell, and all subsequent changes will be random from that point on! Your first change is rather tame, all things considered."

"Ah," was all Mika could really say at this point, glancing at his Barbatos arm as he nodded. The microphone seemed to be surprised at how well Mika was taking all this new info, though he didn't comment on it as he continued.

"They say that a majority of the demonic maturity changes that Sinners go through are typically tied to their misdeeds in life," pointed out the microphone, prompting Augus to raise a brow. "If I may, what exactly did you do to get an arm like that?"

And to that, Mika couldn't help but offer a mild frown as he clenched his new left fist. Via his peripheral vision, the pilot noticed that Niffty was jogging up to his side, and before long, she was examining his new arm with great interest.

"For once, I'm with the Radio fucker, or at least I'm with his microphone. I know you piloted a robot and all that, but for you to use it so much that it's come to define who you are in Hell? What the Hell did you do to it to form such a deep connection?" inquired Husk as he approached the pilot.

Off to the side, Alastor himself also appeared curious, as evident by how he was glancing in their general direction, his grin slightly wider and an eyebrow quirked up. Hell, his microphone also seemed curious as to why Mika's arm had become like this…

And to that, Mika couldn't help but shrug a little, with him glancing at his new left hand as Niffty stared at her reflection on his new gauntlet.

"Sins… save…? That… is not for you to decide."

For something to define him so intensely that it literally became a part of him in Hell…

"Barbatos… hold nothing back… give me all that you have…"

Perhaps…

"Not enough… more… more… more. Give me more…. Barbatos!"

The pilot offered a small smile as he found his answer, and as small as it was, his smile was noticable enough to make Husk, Alastor and the sentient microphone perk up.

"Hey, robo limbs, what's so funny?" inquired Husk with a raised brow, prompting Mika to shake his head as he rubbed his Lupus Rex hand against the metal plating of his legs.

"Come on, Barbatos. I'll remove these bothersome chains for you. That's our prey, our enemy, and we can't hold back against it. So show me…

"Show me your true power…"

"It's nothing," assured Mika, closing his eyes as he shook his head, wiping the smile off his face as he glanced at Husk.

"We… can't stop yet… right, Barbatos? You… don't wish for that, don't you?"

The cat demon seemed a little unsure at that response, though he ended up begrudgingly nodding a little as Mika raised his new arm up to eye level, glancing at the white armour rather nostalgically, ignoring how Niffty was clinging onto it.

"Let's do it then… let's howl together… one last time…"

"This arm, I like it! It's shiny and clean! Keep it that way!" proclaimed Niffty with a smile, and at that, Mika nodded.

"I do too…" replied the pilot as Alastor chuckled, his smirk growing in size as Augus sighed.

'I guess even before now, Barbatos is still with me.'

Short, simple and a little underwhelming, but either way I do hope you enjoyed this short chapter.

Being a bit of a prick, I couldn't help but add a bit of additional lore into the Hazbin Hotel world. It's definitely non-canon, and if it is, then what luck! But as of now, demonic maturity is my own headcanon for the series. I hope you guys enjoyed it.

I'll be honest, I'm terrible at outros… so I won't doddle and just head off to the review replies.

megakdra100: though that would be interesting, I will say that they probably won't. Watching the past is something I'm not too fond of, feels a little unnatural, even for me.

Niuzu0130: why thank you

Dead344156: thanks my dude!

DizzyNepNep: well I'm glad I managed to put a smile on your face! And regarding I.M.P and Sir Pentious, well, perhaps… and regarding Gunpla, MG all the way!

Artyom-Dreizehn: thanks! I too enjoy writing the reactions of people towards the new force in their world. And if I'm honest, I'm also a little excited about writing the chapter for the pilot…

King of 2211: now that I think of it, Husk could definitely fit in with Tekkadan as a sorta opposite to Old Man Yuki, being worried for the team in a more aggressive manner.

robertmusical12: why, you're welcome!

miku8967: I couldn't help myself, tbh. The opportunity was there and I grabbed it by the buttocks as hard as possible.

starscreamer11: well, here ya go

rafaelzan1: I'm glad you enjoyed it! And frankly speaking Niffty was the most fun to write. She's just great. Then again… Vaggie will be quite the trip…

Cylon One: strange chapters are usually my speciality, honestly. And at this point Mika's just here for a good time, so raisins are the best reward for him

Alright last review, being the longest of them all.

coldblue2015: so regarding your questions, I believe that the first half of question 1 has kinda been answered by this chapter. As for the second half, I'll touch on it in a future chapter. For the second question, no, though I believe that question has been answered by this chapter as well.

Regarding Angel Dust, Vaggie and Charlie, yes they will have 1-on-1 chapters, and in regards to the exterminator bit, well… I do have something planned.

Stay tuned for that.

Well that just about sums it all up. Have a nice day, yall!

Oh and there's a P-Bandai expansion set for the MG 1/100 Gundam Barbatos! It looks so damn good, but FUCK P-Bandai is expensive!

Fingers crossed for a retail MG Barbatos Full Set!