*Shink!*
Daki's head flew off her body, and landed on the grassy patch beneath her fear.
She was in deepest pits of despair at the moment not only did he brother just get murdered but she's about to die.
She didn't want to die. She begged and prayed to her Lord and Savior Muzan to save her.
But no one answered.
(Do you Daki wish to bind yourself and become a faithful servant to Issei Hyoudou. Choose quickly or you will die.) she heard a voice.
Almost half of her head was disintegrated, but she asked 'Will I live?'
(Yes.)
Her reply was immediate. 'Then I want live save me!' A magic circle appeared underneath her and her body disappeared in motes of light.
...
Issei entered a room to see Mukago, however she was wearing a cute cat hoodie with a pair black tights which accentuate her perky little ass.
A smirk made it's way onto Issei's face as he used the the Selfless State which completely hid his presence from her.
The Selfless State is a supernatural, esoteric and mostly mysterious state of being in which one completely erases their presence from the battlefield, completely getting rid of their fighting spirit/will to fight, bloodlust, anger, hatred, malevolence, drive and animosity.
Not much is known about how a person can access the Selfless State, but based on how Tanjiro learnt it in the midst of battle, one must be able to close of all of their senses and clear their mind, focusing on a particular moment so much that they reach a stage where they are completely detached from themselves.
Right at this moment Issei is currently focusing on Mukago's perky ass. His hand then slapped her cheeks.
"Kyaaaaa!!!" Mukago screamed in pain and lust from the slap as Issei didn't forget to use touch of pleasure.
His last five hundred slaps completely skewed her concept of pain and pleasure. That's what he hoped for.
Mukago turned around and looked at Issei, her little tights were now soaked with her juice's and her face was now red.
She then gulped when she saw the gigantic shape of Issei's dick forming in his pants.
Issei sat down.
"So how you've been?" he asked as he grabbed her and sat in her lap. Mukago smiled a deep blush appearing in her face.
"Oh! I-I've been training! Just like you told me to Master, the system was able guide to the training room." she says as grinded her ass deep into his crotch.
She knew what her master wanted.
"Wait? Training Room? System explain."
[Master I updated myself to house multiple recreational facilities such as hot springs gaming lounge a bar and many more. A training room was also included.]
"Whoa! You can do that?"
[Sir of course I can doing something like is incredibly easy. Plus it doesn't take more than a single micro second to carry out such simple updates.]
"I see, so how's your blood demon art coming along and how strong are you?" he asked his demon slave.
"Well originally I wanted to make a new blood demon art, but the system told me to simply improve upon what I have."
She then showed me her nailed which glowed yellow lightning now sparkling around them. Then they changed to red to which her fingers started burning.
"The system explained to me the how classes work in your world. Currently I'm physically at in the low stages at mid-class. And my demonic energy is at peak mid class." she says with a smile.
"Demonic energy? That exists in this world?" asked Issei.
[Yes it does. Magic existing in this world isn't that farfetched. The energy demons use in this world is very similar to the one the devil's use in your world.
However it is heavily nerfed in this world due to them needing blood as an important factor for their attacks.]
"I guess that makes sense we do literally see Gyutaro walking towards hell. Though I do wonder what's gonna happen if a demon from this world comes to my world?"
[They will adapt to the demonic energy type due to the laws of that world.]
"Sweet so she'll get stronger!" says Issei with a smile o his. "You hear that Mukago you'll be able to get even stronger than normal." says Issei as he patted her, the demon girl smiled a blush on her face.
"Though I do have to ask what's with the clothes?"
"Well after I heard that master is from a different world that's ahead of ours, I wanted to know what type of clothes existed back then." replied the demon.
"I see."
"You know you've been a really good girl, maybe I should award you." Issei whispered into the demon's ear, the words sent a shiver of pleasure through her spine.
"T-then how about y-you m-make love to m-me." she stuttered, her face had a full blush.
"Alright then." said Issei, he then kissed Mukago's neck causing her to release a small moan.
Her eyes became hazy as she felt a pleasurous delight throughout her body. Issei then unzipped her hoody and took it off throwing it to the side.
Mukago was wearing a black tank top underneath. Issei repositioned her body so she was facing him.
He then gave her deep kiss causing the demons eye's to widened but close a second later, the kiss felt great, it sent tingles of delight down her spine.
Not only that her master's mouth tasted great not like humans, but somehow with more flavour.
She loved it.
Issei then snaked his arms up her tank top, he then sunk his hands into breasts and began groping, them. Mukago released a muffled moan.
Soon she and Issei parted mouth a string of saliva could be seen.
Mukago had a dazed look I her face which she immediately came out of when she felt Issei pinch ad twist and her nipples.
"Kya!" she screamed in surprise and pleasure.
"Strip and lie down I'll give you reward." says Issei. Mukago nodded she got up and began to strip, taking off her tank top.
He liked that aiming for the boobs first. Ever since the merger with Issei he's been slowly preferring tits.
Mukago's breasts were a surprising D cup! They weren't monstrously big like some of the girls from his world but they were fucking huge nonetheless.
"Nice tits." said Issei Mukago blushed.
"I heard master preferred them big so I tried changing their size." said the demon. Issei almost forgot that demons had partial body manipulation.
"Alright then let's do this." said Issei stored away his clothes in the inventory. Mukago blushed deeply as she saw the figure of her master, muscles that were somehow perfect in way, not too big not too small, not only that the giant cock that will be destroying her.
"Since this is your reward how would you like me to fuck you, rough, gentle. All your fuck-able holes just your pussy. You decide." said Issei.
"R-rough a-and a all my holes please!" says Mukago with deep blush.
Without a word Issei sat down on her placing his cock in between her chest, due to his size a portion of his dick was in her face.
It's musk was all she could smell, with a bit of hesitation she licked the head, lapping up some of the precum.
It tasted amazing!
She then began to lick it even more, she grabbed her breasts and began titty fucking Issei's dick.
Issei see Mukago didn't have much experience with this after all.
But her breast and tongue still felt amazing. She then began suckle on it's head savoring it's taste.
Issei then thrusted his hips, a portion of his dick went into Mukago's mouth.
"You said you wanted it rough." said Issei as he then slam his entire rod down her throat.
Due to adding touch of pleasure to his dick, Mukago lost count of how many times she came.
Issei's thrusts were mercy less but soon he reached his climax and he fired off a load inside Mukago's mouth filling it to the brim.
"Make sure to swallow." he told and the girl did just that but slowly. She started with small gulps, before rolling what was left in her mouth to savor the taste.
'So yummy. I want my Lord to impregnate me!' she thought but she suddenly found herself on her stomach.
"It's time for your ass to get pounded, I think your mouth lubed me up enough." Issei placed his shaft at the entrance of her butt hole.
Mukago felt her ass open as Issei pushed in his massive dick with a grunt causing her to release a jet stream of juice from her vagina. It hurt alot but it felt amazing.
The demon had a look of absolute bliss on her face, her tongue was sticking out her mouth while her eyes were rolled back.
It was a very arousing sight.
But as you know Issei didn't stop as he violently began to defile her ass. As he thrusts into her causing the poor demon's legs to go out.
If it were a normal girl they'd long be dead. But Issei didn't care as he violently fucked his demon bitch.
"Yes yes yes! Punish my whore asshole!" Mukago screamed. She loved every second of the pounding.
So Issei was there fucking her ass hole for over an hour.
"It's about time I ended this. I don't think I should neglect your pussy any longer." says Issei as he had Mukago sitting on his lap while he continued to pound into her gaped out asshole.
Mukago had already gone limp from all the pleasure, Issei was simply using her as a onahole.
*Pak Pak Pak!*
He began to speed up his thrusts, with a grunt he fired off another huge load straight into the demon girl's asshole.
Mukago screamed in pleasure as he master released another inside of her.
Issei then turned her around to face him, he was still hard. And he won't stop until his dick goes limp.
He then aligns her pussy with his dick and he slammed his cock into her cunt widening it so no other cock may feel pleasure from it.
"Kyaaaaaaaa!" Mukago screamed in pleasure a large smile on her face as she unconsciously released her elongated tongue, which Issei immediately took into his mouth.
Kissing the demon a he began to thrust into the demon, with how fast his hips were moving it was as if he wanted her pregnant.
"Master I love you! Paint my pussy white your cum! Breed me! I promise to give you a thousand children!" screamed the demon, Issei smile as he kept pounding he pussy.
He then pressed her down onto the tatami mats and he went for her right nipple, he began to suck on it, while he groped her left breast.
Issei fucked her like that for hours on end swapping between multiple different positions.
Each time he would cum he'd kept fucking her. Not even stopping for on bit. Until he just got bored and decided to just stop once Mukago passed out for the umpteenth time.