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Atsumu typically didn’t use his Voice on others. It wasn’t acceptable in public, and there were many laws and regulations to ensure the public safety of omegas.
But that didn’t mean he couldn’t use it at home.
His Voice wasn’t particularly strong because he hadn’t used it since presenting as an alpha. That changed when Osamu presented as an omega. Omegas were particularly susceptible to Alpha Voice, and Atsumu was given the perfect opportunity to strengthen his Voice in case he ever needed to use it.
He started out small, with short commands to get Osamu to, “Fetch me a glass of water,” or to, “Sit down by me and watch this funny video.”
Over time, his Voice grew stronger, and the commands he could inflict on Osamu became more complex and time consuming.
“Cook tuna tonight.”
“Keep practicing with me.”
Osamu didn’t even realize Atsumu was using his Voice on him most of the time. He would become so compliant when he was given an order in the commanding tone that it seemed like he enjoyed being ordered around. Like he was made to be Atsumu’s plaything.
Atsumu decided to step it up a notch. He started using commands Osamu would disagree to if given the freedom to do so.
“Do my homework tonight.”
“Hold your breath for a minute.”
“Lemme see your slick.”
He didn’t know where the last command came from. He just noticed how sweet Osamu smelled and instinctively knew that he was smelling his slick.
When Osamu turned around, dropped his pants, and bent over to bare his wet, slick soaked hole to Atsumu, Atsumu recognized that a fine opportunity just presented itself to him.
Atsumu licked his lips, dilated eyes fixed on that ring of muscle Osamu was showing him. He reached out to rub a hand over Osamu’s ass, and when his brother flinched at the contact, it was second nature to use his Alpha Voice to say, “Relax.”
Almost immediately, Osamu’s tense muscles obeyed his command, and he slumped forward on the desk in front of him.
“Good omega.” Atsumu murmured while his hand slid over the curve of Osamu’s ass, pinching lightly to earn a quiet yelp. “Be quiet.”
Yet again, the command took over Osamu’s mind, leaving him obedient and helpless.
Atsumu put both hands on Osamu now, spreading him open and watching the slick glisten in the light of the sun shining into their room. He jiggled his cheeks and ran his thumbs along Osamu’s crack, pressing at his rim, and spreading it open repeatedly before sliding a thumb inside.
Osamu sighed at the sensation and spread his legs open even more. Atsumu chuckled at the display, amused at how slutty his younger twin was turning out to be.
“Good boy, opening your legs for me.” Atsumu murmured while he slid his thumb out and in, rubbing over the muscle but not quite searching for his prostate. “You’re so wet fer me. Did ya get this slick from me commanding you, or are you just a desperate slut, hoping that your alpha brother will fuck ya?”
When Osamu didn’t answer, Atsumu growled and slapped his ass with his other hand. Osamu whimpered and clenched down around his thumb. “Answer me when I ask ya a question.”
The growling command loosened Osamu’s lips. “Want ya to fuck me, ‘Tsumu-nii!”
And well, that wasn’t the answer Atsumu was expecting, but it was the one that made him take control. He forced another finger inside Osamu, scissoring him open on one hand while his other reached around to paw at Osamu’s cock. He was hard and leaking, a desperate mess waiting to be fucked by his big brother. Atsumu was going to deliver.
“Straighten up and strip. I want ya naked when I fuck ya.”
Osamu did as commanded, a brilliant blush tinting his cheeks red, whether in arousal or in embarrassment, Atsumu didn’t know. All he knew was that Osamu had incredible tits, and he couldn’t wait to mark his little brother up with bite marks and bruises.
“Turn around and bend over the desk again. Spread your legs wide, and hold your cheeks open with your hands.”
When Osamu was in position, Atsumu leaned over him, fully dressed, and finally put mouth to skin. He licked over Osamu’s scent glands, filling the air with omega arousal before pressing bite marks and hickeys down his back and to his ass.
He slipped his fingers back inside Osamu’s hole, stretching him nicely to prepare him to take Atsumu’s cock.
“Look at my little slut. So willing to hold himself open fer me. You like this, no. You love this, don’t ya, Osamu? Have ya been dreaming about this day? The day your big brother fucks you with his alpha cock?”
Osamu whimpers, shaking his head in denial, but Atsumu knows better.
“Ya probably jerked yourself off to fantasies of this, huh? Or I guess, ya probably fingered yourself open to this, since your omega cock is pretty much useless.”
With that, Atsumu gave Osamu’s cock a light slap, and Osamu howled underneath him.
“Ya probably fucked yourself on a dildo while imagining it was me. Well, O-sa-mu, I’m gonna give it to ya better than yer best fantasy.”
With those words, Atsumu unbuttoned and unzipped his pants, took his cock out, and slid inside Osamu all in one glide.
Osamu’s body jerked, trying to get away from the intrusion, but all Atsumu had to do was say, “Stay still.” And Osamu because Atsumu’s perfect fuck toy. Without the ability to overcome Alpha Voice, Osamu was trapped as Atsumu’s perfect and obedient omega cocksleeve.
The next few minutes were a blur of movements and commands.
“Keep holding yourself open for me, Osamu.” The wet squelching noises filled the room as Atsumu pistoned his hips.
“Let me hear you. I want ya to tell me how good I’m making you feel.” Osamu’s cries echoed loudly in the empty room, his breathless whimpers music to Atsumu’s ears.
“Clench down around me, that’s it.” The closer Osamu got to orgasm, the more his body begged Atsumu to keep going.
“You’re not going to come until after I come. Wait.” Osamu was crying, overstimulated and made to wait to come, his body was too-sensitive, his nipples rubbed raw against the wood of the desk, his hole sore, his cock hard as a rock, he would’ve come if something just brushed against it, if not for the Alpha Command just given to him.
The slap of skin continued as Atsumu chased his own orgasm, his knot catching on Osamu’s rim, he forced it inside, making Osamu shout, his cries warning Atsumu that he was going to come, Alpha Voice be damned.
“Wait. Until. I. Come.” Each word was punctuated with a slap to Osamu’s cock.
Osamu sobbed, tears streaming down his face at the command to withhold his orgasm and the feeling of his cock being abused. His body was too sensitive, he was too full, he wasn’t going to make it, but the command was making him wait.
Atsumu’s short thrusts inside moved his knot over Osamu’s prostate, pressing against it continuously, and Osamu clenched down hard to give himself some relief, which finally caused Atsumu to come.
A loud shout and teeth sinking into Osamu’s skin, narrowly missing his neck, signaled that Atsumu was coming. Warmth flooded inside of Osamu, and his body relished in being full of alpha come. Osamu trembled as his own body came, finally being allowed to after being made to wait for so long.
Once Atsumu’s knot went down, Atsumu commanded Osamu to clean him up using his mouth.
Osamu dropped to his knees in front of Atsumu and lapped at his cock, tongue swirling along the length and tasting their combined release. Lucky for Osamu that Atsumu wasn’t in rut, so this stimulation wouldn’t make him hard again just yet.
When he was sufficiently clean, Atsumu commanded Osamu to lay on his back and spread his legs wide. Atsumu stood in between them and ran his fingers over Osamu’s hole, causing whimpers to fall from his mouth as he tried to squirm away from the touches to his sensitive area.
“Stay. Still.”
Osamu tried to breath through the sensations as Atsumu toyed with him longer. He scooped up their combined release and spread it over Osamu’s skin. He pinched his nipples with the slippery release, rubbed it over his sensitive cock, smeared it over his neck, and made him wear it as lipstick. His smoothed it over his wrists and spread it along his inner thighs.
“Don’t shower before school tomorrow. I want everyone to know who you belong to. You’re not to wear scent block either.”
Osamu blushed a brilliant red as the command seeped into his mind. He wouldn’t wash or wear scent block. He’d go to school stinking of their combined release, alerting everyone that he was his twin brother’s bitch.
Tomorrow was going to be a long day.