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Making a deal with a demon wasn’t probably the most sane way of dealing with problems, but Tenko knew that he didn’t have much of a choice. He was desperate enough to do it. If making a pact with a demon would help him get rid of a person, that was making his life a living hell since the day he was born, so be it. It took him years before he collected enough knowledge of the occult to find the courage to do it. Years full of misery, when his only hope was the thought that this day will come. He was more than ready for any punishment that was waiting for his sinful soul. With a voice full of both expectation and fear, he finished with the last part of the ritual. He closed his eyes and listened. There was the sound of the wind blowing outside, raindrops hitting his windows, and finally after a while, the sound of steps. It was coming from the inside of his room. He could feel the presence of someone right in front of him.
"What kind of business do you have with me, mortal?” the demon’s voice was low and deep, sending a shiver down Tenko’s spine. He opened his eyes. In front of him stood a figure at least a head taller than him. A pair of horns was sticking out from a mess of black hair. Almost every piece of the demon’s skin that was sticking out from his clothing was covered in burn marks. Only his hands and a part of his face had healthy skin. The creature had a tail, swishing behind its back nervously, waiting for an answer. Tenko took a deep breath to calm himself down.
“I summoned you to make a deal with you,” he looked up, into the demon’s eyes. They had an unusually cold, blue color.
“Interesting...And what is it that you desire for me to do?” the demon chuckled, showing off his sharp fangs
“I want you to kill my father,” the boy said without any hint of hesitation in his voice. In the presence of a demon, one should never show any weakness.
“And what do I get in return?” the demon asked.
“Naturally, my soul is yours to take,” Tenko answered. However, the demon didn’t seem to be too pleased with his answer.
“Your soul is definitely going to be mine, human. But to fulfill this kind of wish I need something more…I need a sacrifice,” the demon explained, obviously entertained by Tenko’s surprised expression. He didn’t know about this. The book didn’t state that a demon could want something more besides one’s soul. Isn’t that all they want? But he needed to make this work somehow. His plan couldn’t fail.
“Then tell me, demon what do you want? I’m willing to sacrifice anything,” Tenko tried to hide the despair in his voice. Unfortunately, the demon could feel the desperation in his words. He made a few steps forward, getting a little bit too close to him... His hand with long, sharp nails caressed Tenko’s cheek with unusual tenderness.
“Hm...Anything, you say?” the demon licked his lips. Suddenly, Tenko could feel the other clawed hand touching his ass. A rough squeeze forced a gasp out of the human’s lips.
“In hell, it’s quite uncommon to find someone whose body wasn’t touched yet...and yours is quite nice, to be honest,” the creature purred right into his ear and gave Tenko’s ass another squeeze. The poor inexperienced man was overwhelmed by the situation, slowly losing his cool. He took a deep breath.
“If my body is enough of a sacrifice, then... You may use me however you please,” and that was all the demon needed to hear. He moved his hand and pulled Tenko closer by his waist.
“Good boy, Tenko...Call me Dabi,” before Tenko could ask how Dabi knew his name, the demon started to kiss him. It was slow at first like he was teasing the man, waiting for him to react. So Tenko did. Driven by the thought of having to please the demon, he started to return them. He could feel a hint of amusement on the other’s lips...Oh. The demon had a split tongue. Both parts were now playing with Tenko’s own, causing him to moan into the kiss. Unsure what to do with his hands he put them around Dabi’s neck. He let out a surprised yelp when the demon suddenly used this opportunity to pick him up. Instinctively he put his legs around the other’s waist. The demon started to move them towards Tenko’s bed, placing the man onto the mattress and positioning himself between his legs. They separated with a string of saliva still between them.
“A good boy indeed,” the demon panted out, watching Tenko’s face. With a flushed face and desperately gasping for breath, the human looked ethereal. Dabi couldn’t wait to have his way with him. He started to slowly undress him. Placing soft kisses on his exposed neck, he enjoyed the warmth and smell of human skin. His instincts took over and he used his fangs to breach the soft skin.
"A-Ah!" Tenko moaned at the feeling. Dabi was softly lapping at the blood that came out.
“W-What are you doing?” Tenko was obviously confused with the demon’s actions.
“Isn’t it obvious? It’s not like every day a human offers their body to me,” Dabi looked into Tenko’s eyes, “To me, you are like a full course meal and I’m going to enjoy every bite,” to emphasize his words, Dabi licked his lips. Then he moved lower and bit the skin again. Tenko instinctively closed his teary eyes. The demon continued taking off Tenko's clothes while covering the man’s skin with a few harsh lovebites.
After a while, the attacks on Tenko’s skin stopped. He opened his eyes to find the demon above him completely naked. Probably some sort of spell removed his clothing. The demon’s body resembled that of a man with his body parts sewed together, held by stitches. Some parts had healthy skin, others were covered in burn scars. Combined with his massive horns, a fanged, Cheshire smile, and a tail, the creature in front of him looked fascinating. Tenko couldn't help it but stare.
“What, impressed? Or scared?” Dabi laughed, his voice deep. Burying his clawed hands into the skin of Tenko’s thighs he forcefully opened the man’s legs. His pussy, covered with a patch of black hair, was already wet, glistening with its own slick. Dabi’s earlier kisses and bites had an obvious effect on the smaller human.
“Oh...excited it is then,” the demon purred. Before Tenko could even protest, he leaned in and gave his sex a lick, teasing it with both parts of his tongue.
“A-ah!” the human moaned, experiencing such a sensation for the first time. It felt way more intense than when he played with himself. He could feel the creature chuckle against his folds before doing it again. Using both parts of his tongue Dabi started to tease Tenko’s clit, playing with it and sucking on it.
“F-fuck...aah,” acting on pure instinct, Tenko gripped the demon’s horns, applying pressure to keep him where he wanted him. The demon didn’t seem to mind, continuing to lap at the human’s sex. Soon, Tenko started to desperately move his hips against the demon’s face, trapping his head between his thighs. Using the horns for support, the boy was basically fucking himself against his tongues. He could feel his orgasm approaching.
“H-Hah...I’m coming!” he choked out, body shaking as his orgasm hit him. Out of breath and strength, he finally released his grip on the demon's horns and relaxed his legs.
“S-seems that this time I found myself a wild one,” the demon panted out, catching his breath. Looking up he could see Tenko’s blissfully fucked out expression. He licked off the remains of Tenko’s slick from his face and straightened up. This will be a nice, long night.
“I’m glad that you are enjoying yourself, human, but it’s time for me to have some fun too,” he grasped Tenko’s right hand and led it to his own cunt.
“My claws aren’t really made for this, so be a good boy and prepare yourself for me,” the demon purred out.
Still shaking, Tenko carefully pushed two of his fingers into his cunt. Sensing how soaking wet he took him by surprise. There were a few times when he played with himself for a longer period of time, but even then he never got so wet. His walls were still sensitive from the orgasm and stretching himself out forced soft puffs of air from his mouth. Soon he added a third finger, being extra attentive to stretch himself out as much as he could. He could feel the demon watching every move of his fingers.
“That’s enough. Pull them out,” he commanded and Tenko obeyed. The man watched as the demon grabbed his cock to give it a few tugs. Only now had Tenko enough time to properly observe the creature’s lower anatomy. His cock indeed looked human, but the size was monstrous. It was thick and long, covered with veins. Tenko was sure that his own hand wouldn’t be able to fully wrap around it. He could feel himself starting to panic and the demon could certainly sense it.
“Scared?... You should be,” Dabi smiled, his whole face stretching to a cheshire smile. He leaned in and without any warning started to push into Tenko’s wet heat. The poor man started to shake, the stretch was almost unbearable. The demon leaned in just enough to reach his ear.
"I think you don't fully understand what you chose to sacrifice, yet...I'm going to ruin you for every other human out there, my dear Tenko. You are going to end up so desperate, that you start summoning me just to beg me to fuck your cunt one more time," his hot breath made Tenko shudder. The demon’s cock was only halfway in and he could already feel like he was going to be ripped apart. His lower region hurt, tears were falling down his cheeks.
“Oh come on, it’s not that bad. You are a tough boy, you can easily take it,” Dabi moved and started to lick Tenko’s tears.
“I-I can’t...it hurts,” Tenko’s voice was full of pain and despair.
“And here I thought you were sooo brave. Guess I need to help you out a little,” Dabi cooed. He bit Tenko’s lower lip a little, causing the man to gasp before quickly pushing his tongues in. Tenko instinctively closed his eyes, letting the demon explore his mouth once again. Because of that, he wasn’t able to see the demon’s eyes glowing for a second. However, when they finally separated, he started to feel a little bit funny.
“I used some of my powers on you. Your body should become more willing to take me,” the demon explained. Tenko could feel his skin growing hotter. The pain in his lower region was becoming milder. Instead, he could feel himself growing more excited. Suddenly, his body started to move on his own against the demon, taking in more of his length.
“P-please...give me all of it, Dabi,” Tenko pleaded. It was like he became possessed thanks to the demon’s magic. The thought that he was doing this to get revenge on his father was gone. His whole existence and purpose changed to pleasing the demon on top of him.
“That’s it, that's a good human fucktoy,” the demon whispered before slamming the rest of his cock into Tenko’s smaller body. Instead of enormous pain, Tenko’s body was hit with a wave of pleasure.
“A-ah yes...M-move Dabi, please” he could hear himself begging. Tenko knew that there was no point in trying to fight with what the demon’s powers were doing to him. With how good it felt, maybe he should just let himself enjoy it.
“With pleasure,” the demon chuckled and started to rhythmically thrust into him. Instinctively, Tenko wrapped his legs around Dabi’s waist. He could hear the bed creaking, the headboard hitting against the wall. A part of him knew that he should probably be worried about his parents hearing it, but the rest of him really didn’t give a damn.
The demon above him was breathing heavily, his grunts echoing in Tenko’s ears. The sound was so erotic, he couldn’t get enough of it. With every thrust, the thickness of the demon’s cock was hitting something in Tenko’s body that forced him to bury his nails into the other’s body.
“A-ah my belly feels so full! ”Tenko blabbed out among Dabi’s thrusts.
“It doesn’t only feel full, Tenko...Look down,” the demon whispered into his ear. Obeying the command, Tenko looked down to the place where they were both connected. He gasped.
The demon’s cock stretched his underbelly so much, it formed a bulge that was moving up and down along with his thrusts.
“I-it’s so big,” slipped out of Tenko’s mouth. Embarrassed with his own words, he would probably cover his mouth if he could. He could hear the demon snickering above him.
“And it will get bigger once I fill your small, human body with my seed,” to empathize with his words, the demon squeezed Tenko’s sides, his claws breaking the skin. The action forced a choked moan out of the human. Then he leaned in, looking Tenko directly into his eyes.
"You know, maybe I should tell your daddy about this before killing him. Make his last moments even more memorable, by saying how much I enjoyed fucking his little boy’s cunt. How you begged to be filled full with my damned seed, moaning like a low-class bitch in heat...He should know that his precious son would rather let a demon breed him than spend one more day living with him.” the demon spoke slowly, his words making Tenko’s skin crawl with both fear and excitement.
“N-No...please, don’t tell him!...A-ah…,” he tried to protest, but the sensation Dabi’s thrusts were causing him was too strong. His body failed him and he came for the second time that night.
“D-Doesn't sound like you hate the idea that much” the demon would probably laugh if he could, but the way Tenko’s walls suddenly clenched around his cock surprised him. Even with his unnatural stamina, he could feel his limit approaching. Muffling his own low groan by catching Tenko’s lips he spilled his hot seed into the human’s body.
“A-ah...g-give me...all of it,” Tenko managed to muffle out among Dabi’s kisses. The demon could feel the smaller body milking every last bit of his cum. That marked Tenko’s part of the deal fulfilled. But since Dabi was a creature that should never be trusted, he decided to leave his cock in the warm, wet heat for just a while longer. Keeping the human’s mouth preoccupied with kisses, he let himself enjoy their last moments together.
...
With the power of the demon’s spell disappearing, Tenko’s body started to grow exhausted due to what he just went through. By the time Dabi slipped out of him, the human was already drowsing away. Dabi made a few steps toward the door. It was time for him to complete his end of the deal. But something in him forced him to look back at the sleeping face, almost lovingly.
"You are such a good boy Tenko...Maybe when your last day comes I should snatch you from the good old reaper and have you all for myself. Until the end of days…,”