Oh, look, Sanscest lemons

Heat; Cross x Nightmare

TW;
Heat (duh), dom!Cross, sub!Passive Nightmare

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Nightmare paced back and forth, having an intense difficulty standing still. He had locked himself in his room for a few days now. Why, you may be asking, would the king of negativity be hiding out in his room for so long? Well, Nightmare has been dealing with a bit of an...issue. And this issue has rendered him unable to use his magic. And without magic, he was unable to stay in the form that earned him the nickname "goopy octopus". In other words, Nightmare was stuck in his passive form, which nobody in the Bad Sanses knew about. Well, nobody except Cross.
The way Cross had found out about Nightmare's passive form was not exactly the way you'd think. See, Cross had come up with the excellent idea of dumping a bucket of water on Nightmare. The goop that covered Nightmare had been washed away for about three seconds before being instantly replaced, though it had been enough for Cross to see what Nightmare truly looked like. Naturally, Cross immediately got the shit beaten out of him, but he didn't complain.
But now that brings us back to the present day. Nightmare had made probably the worst choice he could in his situation and called for Cross to come see him. At this point, though, Nightmare didn't know what to do anymore. He didn't know what was wrong with him and if he were to tell anyone else in the castle what was going on, they would most likely make fun of him for his passive form. Even then, it wasn't like Nightmare to ask for help. In fact, it wasn't like Nightmare to ask for anything. Even if Cross was an annoyance, it was the closest thing Nightmare could get to some sort of help.
A knock on Nightmare's bedroom door cut him out of his thoughts. He sighed and leaned against the wall on the other side of the room. "The door's unlocked." Nightmare informed the person on the other side of the door. As soon as he said this, the door slid open and Cross walked in the room.
Cross turned and shut the door again, though as soon as he turned around he noticed Nightmare's state. "So, what'd you need- wait a minute." Cross paused and put his hands on his hips. "Huh, I feel like something's wrong." He chuckled.
"Oh, DO YA?" Nightmare hissed out angrily and crossed his arms. "Just listen, you dumbass."
Cross rolled his eyes and smirked a little. "Alrighty, Nighty, I'm listening."
Nightmare scoffed a little before starting to explain. "Something's wrong with me at the moment." He informed. "I'm unable to use my magic and my body heat has been increasing. I'm also finding it very difficult to stay still, yet moving too much hurts, especially in the lower areas of my body." Nightmare stared at the ground, seeming embarrassed at the fact that he's having such problems with such a small issue. Cross had gained wide eyes as Nightmare rambled about what was wrong. The oreoman was surprised that Nightmare didn't know what the issue was. Nightmare was probably the most mature member of the Bad Sanses, it took Cross aback that he didn't recognize it right off the bat.
Cross tilted his head, a smug smirk on his face. "Awww, Nighty!~" he giggled like an idiot. "You're in heat! You seem pretty good at controlling it, too! The only way I can really tell is because there's blush on ya! And because of the things you just listed, I guess."
"I'm in what now?" Nightmare raised a brow, seeming suspicious of Cross, who was even more surprised than before.
Cross sighed, his smirk growing more caring than smug. "Don't worry, I know how to help you out of it." He declared. "Is your room soundproofed?"
Nightmare narrowed his eyes at Cross. "Yes, why wouldn't it be?" He asked. Cross just quietly said "you'll see" before turning and locking the door. Nightmare felt a small bit of panic creep in. What was Cross planning on doing?
He scooted closer to the wall as Cross approached him. "Night, do you trust me?" Cross asked.
"No, not really." Nightmare huffed, earning a light chuckle from Cross. Nightmare flinched pretty harshly, though, as Cross cupped his cheek with his hand.
Cross seemed to make a realization. "...holy shit, you're so short like this." He chuckled, resulting in Nightmare glaring up at him. "I'm joking, Nighty, settle down." Cross smiled softly, his other arm wrapping around Nightmare's waist and pulling him close.
Nightmare made a small yelp of surprise, causing Cross to blush a little. He never saw Nightmare in such a helpless state, it was almost like a blessing, honestly.
Cross paused, staring into Nightmare's eyes. He had never been so close to the negative skeleton, even in his goopy octopus form. Nightmare's eyesockets had such beautiful purple pinpricks. Cross wondered if his eyes were just as gorgeous in his other form. Then again, he only had one eyesocket in that form.
"Are you going to do something, or are you going to keep staring at me?" Nightmare grumbled, snapping Cross out of his thoughts. He almost instantly realized Nightmare had gained an intense, violet blush across his face. It made Cross smirk a little.
Cross chuckled a little before suddenly picking up Nightmare bridal style. "Sorry!" He chuckled as Nightmare squeaked in surprise. Cross carried the smaller skeleton over to his bed and flopped Nightmare onto the mattress, resulting in Nightmare making yet another adorable sound of surprise. Cross climbed onto Nightmare and grabbed his wrists, holding them above his head. To his surprise, Nightmare was somewhat trembling.
Cross sighed and smiled reassuringly to Nightmare. "If you want me to stop, you can just tell me." He said soothingly. Though he didn't reply, the comment seemed to make Nightmare's blush intensify. Cross took this as a sign that he could keep going. He let go of Nightmare's wrists, which the other surprisingly kept still. Cross proceeded to unbutton Nightmare's surprisingly regal outfit, somehow unstained by the goop Nightmare usually produced. Cross generally wondered if Nightmare's outfit produced goop and changed forms, just like he did? As he thought about this, he pulled off Nightmare's shirt, resulting in him snapping out of his thoughts.
Nightmare seemed rather embarrassed about the entire situation. He was staring at a wall to avoid eye contact with Cross, who found it somewhat adorable. However, Cross was more distracted by Nightmare's soul, which was glowing slightly from within Nightmare's ribs.
Nightmare's soul had a very strange shape. It was in the shape of an apple and it had a dark, almost blackish color. Cross couldn't tell what color it exactly was because it was so dark, but considering Nightmare's entire color scheme, he assumed it was either purple or cyan. Cross reached forward and Nightmare's soul appeared in his hand. Nightmare visibly flinched and looked up at Cross in fear, though didn't move.
"I can stop whenever you want me to." Cross reminded before gently squeezing Nightmare's soul. It felt somewhat squishy, though he honestly didn't expect it to feel different from any other soul. A soul was a soul, after all, no matter the shape. Nightmare flinched at the contact and made a small moaning sound, causing Cross' face to heat up. He wanted to hear that sound again. Cross held the soul with both of his hands and started to rub it with his thumbs. Nightmare arched his back and moaned out again, his hand hovering over his mouth. His face was covered in a bright purple blush, and Cross wasn't too far from the same as he rubbed circles into Nightmare's soul. The smaller skeleton continued to make those adorable sounds Cross loved so much while wriggling about under him.
Cross slowly lifted Nightmare's soul and looked at him nervously. "...can I?" He asked nervously. Nightmare, who was somewhat panting, nodded a bit eagerly. Cross chuckled lightly and slowly licked Nightmare's soul, bottom to top. Nightmare flinched and gasped out a moan, shuddering. It tasted somewhat like an apple flavored gummy. Cross wanted to taste more of it.
He started licking at Nightmare's soul as if it were a popsicle, resulting in Nightmare to cry out from the pleasure. Nightmare had reached up and clawed at Cross' jacket, moaning out his name. Cross stopped and stared at Nightmare in bewilderment, feeling his soul skip a beat. The smaller skeleton looked so adorable in this condition. Cross hesitated before gently biting down on Nightmare's soul.
"C-Cro- Ah!!!" Nightmare yelped out, jolting up slightly as tears pricked at his eyes. Cross immediately let go of Nightmare's soul and knelt down, resting his forehead on Nightmare's.
"I'm sorry, I should've warned you, are you alright?" Cross asked worriedly, gently rubbing Nightmare's shoulder blades.
Nightmare, who was somewhat trembling, nodded quietly. "C...can you do that? Again...?" He murmured nervously.
Cross smiled a little and sat back up. "Of course." He chuckled and pulled Nightmare's soul back towards him. Cross looked at Nightmare cautiously before carefully biting down once more. Nightmare yelped once again and, most likely instinctively, bit down on his hand. Cross sighed and grabbed Nightmare's wrist, pulling his hand away from his mouth. "Don't do that, you'll hurt yourself..." he murmured.
Suddenly, Nightmare sat up and wrapped his arms around Cross, resting his head on his shoulder and burying his face into his scarf. Cross was somewhat taken aback, obviously, but wrapped one arm around Nightmare while he held Nightmare's soul with the other. He smiled a little and then released Nightmare's soul, causing the smaller to whine a little in complaint. Cross only made a small humming sound and gently brushed his finger tips along Nightmare's spine with his now free hand. Nightmare whimpered at this, but quickly screamed out in a mix of pain and pleasure once Cross harshly bit down on his collarbone.
Almost as soon as the intense pain had arrived, it was gone, leaving a dull stinging sensation where Cross still had his teeth. Tears had fallen down Nightmare's cheekbones as he shook violently, clinging onto Cross like his life depended on it. Nightmare started to whine and moan once more as Cross started gnawing on Nightmare's collarbone. As Cross did this, though, Nightmare had started tugging at his jacket. Cross paused before chuckling lightly, letting go of Nightmare, who had a somewhat grumpy expression. The bite Cross had left was definitely going to leave a mark, but that was a good thing.
"Hehe, sorry." Cross smiled before pulling off his scarf, then his jacket, then his black tshirt, leaving both of the skeletons without any shirts. Nightmare seemed pleased at this and leaned back towards Cross. However, Cross had other plans. He grabbed Nightmare's shoulders and shoved him down, catching Nightmare off guard. Cross then started fiddling with Nightmare's belt. Once he got it off, he immediately started tugging down Nightmare's dark gray jeans, leaving the smaller skeleton in his underwear. Nightmare's trembling had started to return, though Cross paid it no mind as he started to remove his own pants. Almost as soon as his pants were gone, Nightmare noticed a glowing bulge in Cross' pants. To say it frightened him was somewhat of an understatement. Cross noticed this and cupped Nightmare's cheek with his hand while fiddling with his underwear with his other hand.
He made Nightmare look up at him, which Nightmare was somewhat thankful for. Cross looked so reassuring, his gaze scanning Nightmare for any sign that he should stop. The only thing Nightmare could focus on was Cross' voice, which quietly murmured sweet words of encouragement and reassurance. Nightmare hadn't even noticed that he had summoned anything in his pelvic area until a sharp, intense pain shot through his entire body. He cried out in pain and wrapped his legs around Cross' waist, who held him close and continued to murmur. As the pain slowly but surely subsided, Nightmare had realized that he had summoned female privates without even realizing. He was bewildered by this, but was quickly interrupted by another realization. Cross wasn't moving, not even a little. He was still murmuring those words to Nightmare, but otherwise stayed completely still. Nightmare attempted to move, but flinched harshly as a sharp wave of stinging pain shot through him again. He looked down and saw that Cross had shoved his entire length into him. Either Cross was really big or Nightmare was really tight, because it hurt like hell. Nightmare couldn't tell, though, as his vision was dotted with black spots.
Nightmare waited quietly until he felt like he couldn't anymore. He moved up slightly, then down again. He gasped out as pain shot up his spine, though it wasn't as bad as before. It was actually kind of nice. Cross took a sharp intake of air as Nightmare did this, making him realize it was probably torturing Cross to stay still for so long. After thinking about it, Nightmare wrapped his arms around Cross and fell somewhat limp, catching Cross off guard.
"Are you ok?" Cross asked worriedly, his voice still unnaturally quiet and soothing compared to how he usually talked.
Nightmare nodded with his eyes closed. "Mhm..." he mumbled before burying his face in Cross' neck. Nightmare then said, his voice barely above a whisper, "do whatever you want..."
Cross was caught off guard, that was for sure. He was certain that Nightmare wanted at least some control, being the leader and all, but here he was, wrong, with Nightmare practically limp against him. "A...are you sure?" Cross sputtered out worriedly. Nightmare just quietly nodded as a response. It was Cross' turn to tremble slightly. "Just...let me know when to stop, alright?" Cross murmured in concern.
Nightmare just chuckled lightly and nuzzled Cross' cheek. "Stop acting like I'm going to shatter, I'll be fine." He assured, though it didn't help Cross much.
Cross hesitated before pinning down Nightmare, who squealed from many things. For one thing, it was very quick and Nightmare had to process what had happened. Secondly, Cross' "thing" was still fully inside of him, and the sudden movement fucking hurt. Thirdly, the gaze Cross gave had changed as suddenly as the position. He was staring at Nightmare like a predatory animal stalking it's prey, and it startled him somewhat. Then, Cross had roughly grabbed Nightmare's ribs and held them tightly before reaching up and biting his neck. Nightmare screamed out in mostly pain and arched his back, clawing at the bed sheets. So, this is what instant regret feels like. Nightmare sure as hell did not enjoy it. Cross licked along his little love bites on Nightmare's neck before starting to ruthlessly pound into the smaller skeleton.
Nightmare clung onto Cross' shoulders, digging his nails into them, and had started shrieking from the pain and the pleasure.
Tears streamed down his cheeks. It was so painful, yet Nightmare loved it anyway. He was seeing stars at this point, unable to string together proper words. The only words that were exactly comprehensible from Nightmare was Cross' name and a bright rainbow full of swear words. It only took a few thrusts for Nightmare to start heavily panting through his moans and screams. Cross took the opportunity and roughly kissed Nightmare, who had to constantly pull away for breaths of air. However, Nightmare always returned to kissing Cross as if his life depended on it until he needed a gasp of oxygen five seconds later. Cross smirked through his own pants and moans. He had always dreamed of seeing Nightmare in this condition, helpless and submissive and under Cross' mercy.
Nightmare seemed to suddenly tense up, also tightening around Cross which only doubled the pleasure the two felt. He suddenly cried out and leaned forward, biting onto Cross' shoulder, which caught him off guard. Though, Cross soon figured out what was up with Nightmare as the smaller skeleton violently came. "H-HaaAH!!!~" Nightmare muffedly cried out through Cross' shoulder. Cross had forced himself to slow down somewhat, allowing for Nightmare to settle down from the climax. Nightmare panted, gasping for air and every bone in his body aching from exhaustion. Cross gently caressed Nightmare's spine, who was trembling and leaning towards Cross' touch.
Cross chuckled a little and took Nightmare's chin, making him look up at him. "I'm not done yet, Nighty!~" Cross hummed out, making Nightmare shudder. And so, the quick and ruthless pace returned, making Nightmare screech and somewhat sob from the intense pleasure. At least it wasn't painful anymore. Tears blurred whatever vision Nightmare had left, not like he really cared. His mind was clouded with fog, the only thing he cared about was Cross.
Before the king of negativity knew it, he had climaxed a second time, though this time Cross did not stop. Instead, he somehow managed to speed up. Cross roughly rubbed at Nightmare's spine and bit harshly on every inch of his neck. The pleasure was growing too much for Nightmare, he felt like he was going to pass out from over stimulation. Cross had started to move down from Nightmare's neck and had started biting at his ribs. Nightmare had cried out after climaxing a third time. God, it felt like it was so much easier to do so after the first time. Nightmare was surprised that Cross hadn't cum yet, let alone surprised that he had even noticed. Was Nightmare just sensitive? His train of thought was cut off as he moaned out loudly, his tongue lolling out of his mouth.
Cross' thrusts were getting sloppy, he was finally getting close. He thrusted rougher and rougher as he felt a climax coming closer. Eventually, Cross had finally came, biting down on one of Nightmare's ribs harshly, a crack being heard from it. Nightmare had screamed out and had came at the same time, it being his fourth now. Cross had slowly thrusted a little, riding out both of their orgasms. Once he had pulled out, the two of them were panting messes, especially Nightmare. Once Cross had settled down from the high, he noticed what he had done to the smaller skeleton. Nightmare was covered in hickeys and bites of various sizes, which were slowly starting to cease bleeding. Nightmare's ribs weren't too far from the same condition. Cross traced the rib that he had bitten as he was climaxing, Nightmare yelping out and shuddering at he did so. He had bitten on the rib so hard that he had cracked it, might even be fractured.
Cross frowned and laid down beside Nightmare, pulling him into a tight hug. "I'm sorry, I went a bit rough, didn't I?" Cross mumbled quietly. "Are you ok?"
Nightmare smiled a little and giggled through his panting and gasping. Tears still stained his face. Nightmare turned, despite every bit of his being screaming in denial, and kissed Cross. "I said I wasn't going to shatter and I didn't." Nightmare murmured weakly. He was exhausted and everything hurt badly, but he honestly wouldn't mind going for a round two. Maybe after a bit of rest, though.
"So, Nighty." Cross smirked. "Is your heat gone?" Nightmare paused before nodding. "Arentcha gonna turn back to your goopy octoform?" Cross asked curiously.
Nightmare huffed and snuggled up to Cross. "It takes a bit of energy to keep that form up. I'm too tired for that..." he mumbled as Cross' face started to cover itself in blush.
"So...uh...does this mean you'll be my boyfriend, or?" Cross grinned, tilting his head.
Nightmare glared up at Cross. "Don't get ahead of yourself, dumbass."
Cross laughed a little and closed his eyes. "Fair enough, I guess!"
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Earlier...
Horror, Dust, and Killer were vibing in the kitchen, raiding literally everything.
"Where do ya think Cross is?" Dust asked curiously.
Killer shrugged and sat on the counter. "Nightmare called him to his room, haven't seen him since." He informed.
"They're fucking." Horror informed nonchalantly, munching on an uncooked drumstick.
Killer and Dust stared at Horror in bewilderment. Horror just shrugged. "I went by Nightmare's room not too long ago, Nightmare was fucking screaming. It was a bit quiet, prolly cuz of soundproofing, but I could still hear it when I went past." He explained as if it was natural.
"...you know what? Let's just act like this conversation never happened." Dust murmured and sipped on a Pepsi.
Killer sighed in wish to be unalive. "Agreed."

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