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Tony’s cock was rock hard the moment he walked through the door. His nostrils flared, inhaling the most beautiful, intoxicating scent he had ever smelled. An Omega’s first heat. A first heat always smelled different, better, sweeter. The scent was meant to entice Alphas, to get that Omega bred and fat with child as soon as possible. Tony took a deep breath, opening his mouth to press the scent into the roof of his mouth.
He knew the Omega that presented. He knew the base scent of the Omega.
Peter. His son.
His little boy had presented as an Omega and was deep into his first heat. Tony groaned, fingers fumbling at his fly to release his cock. It was wrong, of course. He should walk away. He should call one of the services that would provide a sterile Alpha to knot his son, to give Peter the experience of being knotted without the risk of pregnancy.
He should do that, he really should.
He looked down, realizing he was stroking his cock, smearing precum all over his rigid shaft.
He wasn’t going to call the service.
Tony stalked through the house, panting through his mouth as Peter’s scent grew richer and more potent the closer he got to the boy’s room. He had heard that Omegas were coming into their first heats early, but he never expected his little boy to present this early. After all, Peter was just about to turn nine years old.
He stopped right outside Peter’s door. He was naked, his clothes strewn in a path behind him, half torn off in his haste to get to his son, his beautiful Omega. He didn’t even remember ripping his clothes off. Peter’s heat was going to set off his rut and Tony couldn’t wait. He would knot that little Omega over and over again until he was sure his seed took.
He opened the door and took a deep breath. God, the boy smelled divine. The scent was heavy, permeating the room. Tony looked closer and could barely make out Peter in a tangle of blankets, completely naked, skin glistening with sweat and ass leaking slick. Tony’s Omega had built a haphazard nest with his Spider-Man blankets and he couldn’t wait to knot him right there in the middle of it.
He stepped into the room and walked to the bed, staring down his son. Peter was asleep, tossing and turning in his nest. He whined, sweat beading along his skin. His little cock was hard and red and looked almost painful. Tony wasn’t interested in his boy’s cock, however. He took a deep breath, pressing the scent of newly presented Omega into the roof of his mouth. His dick twitched and he knew he needed to be inside that tight hole as soon as possible.
He grasped Peter by the waist and dragged him closer, lifting his ass to get a perfect view of that virgin hole. Slick leaked from Peter’s pucker, running over his infertile balls and staining the nest of blankets. His hole twitched and almost seemed to wink at him, begging for his Alpha’s cock.
“What a beautiful boy you are,” Tony whispered. He ran his thumb around Peter’s hole and then lifted it, licking the boy’s slick from his skin. He closed his eyes, moaning at the taste. It was so pure, so innocent, so fertile for him.
He couldn’t wait any longer. He had to fuck Peter, he had to knot his son.
He knelt on the bed, running his hands over Peter’s sleeping body. Peter moaned, leaning into the touch. Omegas always wanted to be touched, to cuddle, to be full of cock. Even asleep, Peter was seeking his father’s touch, his Alpha’s touch. Tony eased himself down next to his son, never ceasing his constant petting. His cock ached, desperate to be sheathed in that slick, virgin hole. Peter leaked copious amounts of slick, hole twitching like his body knew that the cock that would ease his suffering was so close.
Tony grasped his cock, rubbing the swollen head back and forth over Peter’s soaking hole. He groaned at the feel of that slick gushing over his cock, soaking him, making it hard to maintain his tight grip.
He pulled Peter close with one hand and guided his dick with the other. He closed his eyes when he felt the tip of his cock press against Peter’s tight sphincter. He held his breath as he rolled his hips, moaning as Peter’s virgin hole opened to him, devouring the head of his cock like it was desperate for it.
“Oh, Petey!” Tony growled. He wasn’t going to be able to go slow. He had planned on it, but now that his cock was sliding into that sweet Omega heat, he was going to fuck his boy hard and fast and knot him, filling him with the very seed that had helped create him.
Peter whimpered, shifting and moving his hips as Tony pressed deeper and deeper. He wasn’t awake yet but Tony knew he would be soon.
“Peter, Petey!” Tony said, closing his eyes as he bottomed out. His son was so tight around him, those virgin walls fluttering around his thick cock, dragging him deeper, closer to his empty womb. Tony dragged his cock nearly all the way out before slamming home.
Peter let out a cry and his eyes snapped open. He howled as feelings he hadn’t known were possible flooded over him. Ever since he’d come home from school that day he’d felt weird, too hot, too cold, too empty. He’d stripped naked and felt the desire, the urge, to gather his favorite blankets into a nest. He’d fallen into an uncomfortable sleep after playing with his little cock. It hadn’t offered any pleasure and he didn’t know why. His daddy always seemed to feel better after playing with his own cock. Daddy didn’t know Peter watched him some nights. Peter had felt so empty all day but now something was inside him, filling that empty space.
“Petey, Petey,” his dad panted in his ear. Peter cried out, moaning and writhing against his father. A part of him realized his father’s cock was inside him, but the newly awakened part of him, that part that had begged to be filled all day, celebrated. He didn’t understand why his daddy was sticking his cock in him, but he didn’t care. He had never felt so amazing in his life!
“Daddy?” Peter whimpered.
“Baby boy,” Tony said, “My Omega.”
Peter tilted his head and Tony nosed at the scent gland on Peter’s neck, running his tongue over it. He absolutely should not bite his son and mark him as his mate. One day Peter would make someone a perfect little Omega, pushing out babies for his fertile Alpha. But it wouldn’t happen if he was already marked by a different Alpha. Peter would only belong to him. Peter would be his son, his mate.
Tony groaned, doubling his pace. Peter whimpered and whined, driving himself back as hard as he could. It hurt but it felt so good at the same time. Peter wasn’t entirely sure what was going on but he knew that his Daddy’s cock was taking away the empty ache inside him. Tony’s hand curved over Peter’s stomach and he swore he could feel his cock push into his little boy with every hard thrust, the boy’s stomach expanding with every thrust. His boy was so small but he took his Daddy’s cock like a champ, like he was made to take his father’s dick.
“You want it, don’t you, Peter?” Tony said.
“Want what?” Peter barely managed to say. He could only concentrate on the feeling of his father’s fat dick inside him. He had never even known it was possible for Daddy’s dick to go inside him, but he never wanted him to take it out.
“You want Daddy’s knot? Yeah, you do, don’t you?” Tony said. “You want Daddy to knot you and you want to give me another pup, don’t you?”
Peter wasn’t sure what that was. School had only briefly touched on the differences between Alphas and Omegas and he knew that a knot was only for a mated pair in love. He couldn’t think. The longer his father slammed into him, the harder it was to think. His mouth fell open and he moaned, nodding.
“Yeah, you want my knot,” Tony growled. His little boy felt so good around his cock. No Omega had ever felt this good, even Peter’s mother. Tony knew that Peter had been made for him, the perfect little Omega just for him. Tony wasn’t going to last much longer, not with that tight, slick hole wrapped around his cock, not with Peter screaming in his ear, the little boy’s cock weeping clear fluid.
“Daddy, Daddy!” Peter cried, looking down at his little cock. It had never been so hard before and it was leaking. Distantly, Peter thought he was peeing himself, but it didn’t smell the same.
“Peter, oh, my Petey. Say you want my knot, son, say you want to give me pups.”
Peter couldn’t think. His body vacillated between intense pleasure and pain, cock leaking and bouncing with every hard thrust from his daddy, his alpha.
“Say it,” Tony hissed in Peter’s ear, “You want my knot, don’t you, baby boy?”
Peter wailed, tears running unchecked down his face and fluid leaking from his little cock.
Tony managed to slow his relentless thrusting, his cock sheathed deep inside his little boy. He cooed at him, running his hands over Peter’s milk smooth skin.
“Shh, Peter, you’re okay.” His cocked twitched inside the boy and Tony was so close to blowing his knot and locking them together. “You want to be good for Daddy, don’t you?”
Peter bit his lip, looking down at the bulge in his stomach that he knew was his Daddy’s cock. Now that Daddy wasn’t thrusting, it didn’t hurt as much. He could feel his slick leaking out of his hole, that same hole stretched wide around his father’s cock.
“You want to be a good little Omega for me, don’t you, Peter?”
Peter wanted to be so good for his Daddy, his Alpha. Tony pressed gentle kisses against the back of Peter’s head, rolling his hips ever so slightly. Fuck, his cock felt so good inside his little boy.
“You’ll make me the happiest man in the world, Peter, just say you want my knot.”
Tony was going to knot his baby boy no matter what, but the thought of Peter begging for his knot made him even harder. He wanted his Omega to want it. He could picture it, months down the line when Peter was fat with a new baby, hormones making him extra needy and horny for his Alpha. Then Peter would give birth to their pup and Tony would watch him nurse. And as soon as Peter went into heat again, Tony would knot him over and over. He’d keep his little omega pregnant all the time. Their house would be full of pups and when those pups were old enough to present…
Tony groaned into Peter’s ear. He had a feeling any pup of Peter’s would present as an Omega and then Tony would breed them too. He’d make his own little harem of willing, needy, young Omegas, begging for their Daddy’s cock.
“Make me happy, Peter,” Tony said.
“I want your knot,” Peter whispered. His heart pounded. He was scared but the longer he sat on his father’s cock the better it felt. His whole body tingled and he’d never felt so good before.
“Oh, Petey,” Tony sighed. “My baby, my Omega.”
Tony thrust as hard and fast as he could into his little boy’s hole. He wasn’t going to last much longer. He was going to fill his baby boy with seed.
Peter whined and mewled, writhing on the fat spear of his father’s cock. It felt so good now!
“Daddy!” he sobbed, “Alpha! Breed me!”
He wasn’t sure where those words were coming from. He wasn’t even entirely sure what they meant but it felt right to say them. He wanted his father to breed him, to knot him. His body knew what he wanted when his mind didn’t. He couldn’t think of anything but his Daddy’s fat cock.
Tony groaned at Peter’s words. Yes, yes he was close.
“Knot me!” Peter screamed. “Knot me, Daddy! Breed me!”
“Yes, Peter, yes, yes, yes!”
The sound of skin on skin echoed around the room, the slick noises of Peter’s soaking hole dragging Tony’s cock deeper barely audible over Peter’s begging.
“Peter!” Tony yelled, snapping his hips forward. His balls tightened and he felt his knot expand, growing wider and wider inside Peter’s tight little hole. His knot had never popped so big and hard in his life. What felt like rivers of cum exploded from his slit, seed seeking his baby boy’s waiting, fertile womb.
Peter felt his Daddy’s cock slam deep inside him and then the base was getting bigger and bigger! He screamed. There was no way his body could take the size of his father’s knot!
“Daddy! It hurts!” he sobbed.
“Shh, Petey,” Tony said, voice breathy. “It’ll feel good soon.”
His baby boy just had to get used to the knot, that was all. Because now that he was locked inside his son’s hole, he was going to knot him over and over. No Omega had ever felt this good around him. Peter lay under him, face down in the pillows with Tony’s weight pressing him down. Each little sob and hiccup sent tingles through Tony’s body, the little omega’s hole clenching around his thick knot. Maybe Peter would feel better if Tony wasn’t on top of him like this. It wasn’t the best position to be locked together in, especially when Peter was so little compared to Tony.
“I’m going to shift positions, okay, Peter? You’ll feel better when we’re sitting up.”
Peter felt Tony’s hands on his waist and then they were suddenly moving. Tony moved fast, wanting to put as little pressure on his knot as possible. Even moving fast he couldn’t suppress the hiss of pain as his knot moved inside Peter. He was always so sensitive after he knotted any little movement from the omega could make him cum even more. Peter wailed as they moved, that fat knot pulling at his rim. It felt like it was going to tear right out of his hole. Tony leaned back against the headboard, Peter’s small back against his chest.
“See, all better now,” Tony said, resting one hand on Peter’s stomach. Soon, that stomach would start to swell, would show the world how fertile Peter was and how good of an Omega he was.
Peter hiccuped, staring down at his little cock. It was hard and red and leaking everywhere. His bum hurt. He could feel his Daddy’s cock deep inside him, his knot just on the inside of his hole, locking them together.
“See, Petey?” Tony whispered, nuzzling Peter’s ear. He slid his hand from Peter’s stomach to his little cock, covering it with his hand and stroking it. Peter let out a cry, hips jerking. Tony hissed as the movement tugged on his knot and more cum leaked out of his slit into his baby boy.
“Does it feel good?” Tony asked, rubbing and stroking his little boy’s cock. “Are you happy with Daddy’s fat knot in you? You’ve made Daddy so happy, baby boy.”
If his Daddy was happy, then Peter was happy. And it was starting to feel good, being stuffed full of cock and cum and the way his Daddy’s knot was big and fat in his ass. His Daddy’s hand on his dick felt good too.
“Uh huh,” he moaned. “Feels good, Daddy.”
“You’ll never forget this,” Tony said in Peter’s ear, “You’ll never forget that your first knot was from your father. No matter how many Alphas you have over your life, you’ll always know I knotted you first. Maybe when your mate knots you, you’ll think of this. You’ll think of your Daddy’s fat knot and how good it felt and how much you love me. No Alpha will ever compare to me.”
Tony couldn’t stop rambling about it. Part of him liked the thought of Peter getting knotted by another Alpha, but unable to think about anything but his Daddy’s cock. How Peter would have to explain to his mate that his first pup was beloved because it was both pup and sibling. Maybe those pups with that future mate would visit grandpa Tony and he would knot them too, just to keep it all in the family. Maybe Peter would like to watch his father, his favorite Alpha, knot all his pups.
Peter hiccuped a little sob. “I don’t want any other Alpha, Daddy.”
Tony moaned, rocking his hips a little and making his knot move. Peter moved with him, making the sweetest little noises.
“You don’t want another Alpha, Petey?”
Peter shook his head. He had never imagined having an Alpha before, but now that his Daddy had knotted him, he couldn’t imagine taking anyone else’s knot. His Daddy had always been so good to him, taking care of his every need, his every desire. This really wasn’t any different. Peter had needed to be knotted, to be filled with cum, and his Daddy did just that. He had always loved cuddling with Daddy, curled around him. Even before he had presented he loved how Tony smelled after a rut.
“I love you, Daddy, Alpha,” Peter said.
“Oh, baby, I love you so much,” Tony said, rubbing Peter’s stomach, thumb caressing that little dick. He nuzzled Peter’s scent glands, licking the boy’s sweaty skin. No matter how amazing it felt to have his knot locked in his son, he absolutely couldn’t—shouldn’t—give his baby boy a mating bite. No other Alpha would want him. He would be considered tainted goods. It didn’t matter how many times an Omega was knotted or even how many pups they’d had, but that mating bite tied an Alpha and Omega together for life. He couldn’t do it. Peter could make some Alpha very happy.
“Feels so good,” Peter said, relaxing fully against his father. “Want you so much, Alpha.”
Tony knew it was the hormones talking, but he loved hearing his baby boy tell him how much he wanted him.
Then Tony felt a warm rush of fluid over his palm and a sharp smell permeated the room. He looked down and saw that Peter was pissing all over Tony’s hand, hot, gold fluid gushing out of his little cock and flooding their laps, running over their thighs.
“Peter!” Tony moaned, pressing his teeth against his scent gland. Ages ago, Omegas would piss to submit to an Alpha. They would piss to show that they were ready to mate and fertile. It had gone out of style as humans had evolved. Omegas didn’t need to piss, didn’t even need to submit if they didn’t want to.
Peter gasped, trying to stop his flow. He let out a soft whimper as his pee ran over his father’s hand and stained his blankets. “Daddy, I’m sorry! I don’t know why—”
“Shhh, baby boy, it’s okay. It’s natural. It means you want me to be your mate. It means you’re submitting to me.”
Peter wasn’t sure what that meant, but his Daddy’s cock felt even harder inside him than it had before. His knot felt even bigger.
Another spurt of piss escaped his dick and Tony couldn’t stop himself. He sank his teeth into his son’s neck, biting the scent gland and leaving what would become a permanent scar there.
Peter felt his father’s teeth in his neck, his scent gland, and couldn’t stop more piss from coming out of his slit. It felt so right.
Tony pulled back and licked at the wound. It would heal quickly and cleanly and everyone would know that Peter Stark was a mated Omega. Peter sighed, eyes fluttering closed. He was suddenly completely exhausted.
“You can sleep, baby boy,” Tony said. Peter would sleep with his knot locked deep inside him. He would wake Peter up later after his knot went down and he’d fuck the boy again, filling him with more cum.
“Okay, Daddy,” Peter said. He was exhausted, stuffed full of cum and cock, and covered in sweat and piss. His neck and hole hurt, but he had never felt more content and happy than he did in that moment. “Love you, Alpha.”
“Love you too, my beautiful little boy, my sweet Omega. My mate.”
Peter quickly fell asleep and Tony sat there, holding his new mate in his arms, knot locking them together. Peter would be pregnant by the end of his first heat, Tony could feel it. He sat there, in his baby boy’s nest, piss soaked Spider-Man blankets tangled under them, and he grinned. Peter had pissed for him. A sure sign they were meant to be mates. Even the school wouldn’t be able to deny his claim on his mate.
Speaking of school, Tony needed to make sure Peter would be excused the rest of the week. He carefully reached over to the bedside table and grabbed his phone. He quickly called the school.
“Hi there, Ms. Potts, this is Peter’s father, Tony Stark.”
“Oh, Mr. Stark, we were wondering if you were going to call. Peter didn’t look well when he left school this afternoon.”
“Yes, well, Peter presented with his first heat today, I’m afraid. He won’t be back until it passes.”
“Oh, so early,” Ms. Potts said. “How is he handling it? Did you call the service in?”
“Don’t you worry, Ms. Potts,” Tony said, thrusting lightly just to feel his knot move inside his precious mate. “A very good Alpha is knotting him as we speak. He’s handling it very well.”
“That’s good. Every Omega needs a good Alpha to take them through their first heat.”
“Only the best for my sweet Peter,” Tony said, his voice going breathy as another spurt of seed escaped his cock. If Ms. Potts suspected anything, she didn’t say.
“Tell Peter we’ll send his homework via email and he’ll have another 2 weeks to get it done. I hope having him in heat won’t be a hardship for you, Mr. Stark.”
Tony grinned, pressing a kiss against Peter’s new mating bite. “Not a hardship at all, Ms. Potts. Now, if you’ll excuse me, the Alpha’s knot is going down and Peter is about to get round two.”
He hung up before she could say anything and started to fuck his sleeping mate again.
It was going to be a very good week for both him and Peter.