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Tetsu and Kirishima had always been inseparable. It was no shock to anyone that the two were destined to be together.
They’d first met on the playground in elementary. Two rough heathens bumped fists together at the thought of an endless friendship.
An endless comradery that would last through middle school despite Eijirou’s emo phase and Tetsu’s troublemaker one.
The kind of companionship that led them to date twin sisters in high school and promptly break up when they found out they didn’t like girls at all.
And even after the confession that came at the end of their senior year. Shared confessions that surprised the hell out of best friends that their unrequited feelings weren’t all too unrequited.
Their friendship withstood it all.
All the fights and the tears. All the hushed whispers of future plans and wishes. Of promise.
It was the best of both worlds being in love with your best friend and soulmate.
That’s how the two men viewed it now at least, four years into their relationship. One that could have started years before had they shared their feelings.
At the age of twenty-two, both men thought they knew it all.
They thought they’d done all they could to make the relationship into one that would surely never end. Into a relationship that would never disappoint. One that would steer clear of the mess that was cheating and heartbreak thanks to their unbreakable and durable bond.
They were wrong. Oh, how both men were oh so wrong.
Tetsu noticed the man in the gym without meaning to.
The silver-haired fox would work out around the same time he would and leave well before Tetsu could get a real look in.
And Tetsu admitted that the first time he noticed the guy was because of his body, benching close to the same that Eijirou would with a body that was so different from his husband.
He didn’t expect the guy to have muscles of someone his age group but benching over 200 pounds at his size should have been straining! It should be considered dangerous.
And Eijirou, being a gym rat with a husband who was well over certified with the same knowledge, would have applauded him for stepping up.
Tetsu could see it now, the moment he’d have after telling Eijirou he helped an older guy at the gym. He’d get some response along the lines of ‘how manly’. He might have earned a few kisses for that one too.
And yet, instead of the comment being anything helpful, the fucker just smirked at him.
The nerve of that guy.
Tetsu would never be disrespectful. He might be raised in a different way than Eijirou, but he wasn’t going to fight some old asshole who thought it was funny when he offered help.
So, he did it again.
And again.
And Tetsu went as far as spotting the damn guy until the blonde sat up and shot him one of those signature smirks. As if he could plow Tetsu into the ground.
Which.. wasn’t the worst idea.
That’s when Tetsu’s thought process started to wire a little more fully than it had before.
It was the moment he realized just how good he got to stare at the other when he was up close. And how good he got to see those muscles working in action despite being that of an older man.
And for the first time since he’d been with Eijirou, Tetsu felt an attraction to someone else. An attraction that he couldn’t help and one that Eijirou knew nothing about.
Tetsu didn’t mean to keep it hidden. It wasn’t like Tetsu to keep things away from his husband.
Yet, he did for some reason.
He did it as the man named Katsuki explained what he did for work. As the man explained his recent divorce from his own husband and bouncing back from that ended relationship.
Tetsu listened.
He listened to everything the older man had to say about love, lust, and the undeniable attraction that some people couldn’t help.
Tetsu hadn’t said a word to Eijirou about his new gym friend in the last three weeks though.
He didn’t explain anything about the man whenever he’d go on about how many reps he did or how many miles he ran.
Tetsu left the guy from his gym stories from the time he first met him. Tetsu planned on keeping it that way for a while too.
Until Eijirou caught him.
Tetsu was working out as sweat slipped down his temple, the dampness collecting in the faux leather under him. He always hated bench pressing despite it being one of his husband's most liked workouts.
It was slowly working to be his favorite thanks to the towering figure behind him.
Katsuki stood where Tetsu would if he was helping the man instead. The man’s hands were hovering over the bar with every new move down, the weights above straining the muscles of his biceps.
Fuck, it did wonders. The difference Tetsu was seeing in his body alone was massive.
That wasn’t the main attraction to the workout though.
From underneath, Tetsu had a clear view of the body standing behind the bench. The thick chest sporting blonde and silver hair exposed from the top of his tank. The broad chest worked down to a slim waist and into the sharp v that finished near the beginning of sweats. His eyes were almost there, focused on the expansion of skin above the sweats band left exposed.
“Tetsu?” came a question. A question that didn’t come from the blonde above, seeing as his mouth was in view, unmoved. Katsuki’s eyes weren’t focused on him though. They were focused on-
Kirishima.
Tetsu looked over and caught eyes with none other than the love of his life. His best friend. His everything.
The look was far from what Tetsu expected.
While the normally pissed-off Eijirou was one that he knew all too well, with furrowed brows and a vein bulging at his temple, the look was far from that.
The furrowed brows were softened into a light expression. There was nothing heavy about the way his eyes looked between the two men currently working at the bench.
Eijirou looked confused. And.. worried? Maybe a little relieved?
It wasn’t up to Eijirou to break the silence though. The older man taking the bar from Eijirou without trouble until he could place it back on the holding bars.
“You mean to tell me you guys know each other? And here I was thinking that I happened to meet two handsome men separately,” Katsuki teased, the obvious silence after left his brow to rise in interest.
“What?”
“You know him?” Eijirou and Tetsu said in unison, mouths shutting at the same time before Eijirou was the first to chuckle. The quick shake of his head made Tetsu snort before looking up towards the ceiling of the gym.
“Were you cheating on me?” Eijirou asked, covering his mouth a bit to stifle a laugh as Tetsu shook his head in reply. “It’s not cheating if you don’t sleep together. I was admiring,” the other suggested.
“So, you do know each other?” Katsuki asked, finger gesturing between the two as his eyes followed suit. “Cheating?” the older man asked, out of the loop of whatever was happening in front of him. “So, you’re what- seeing each other. Dating?”
“He’s my husband,” Tetsu spoke first, Eijirou nodding along. “My husband,” the redhead began, “who is just as big of an idiot as I am.”
“Hey, I’m not an idiot! I was going to tell you about it. I just.. I didn't know if it was unfaithful to look. I didn’t see anyone else as being as hot as you so imagine my surprise when this guy here is an absolute asshole and hot. He wouldn’t listen to me about benching too much. I couldn’t help it.”
“That’s how he got you? I asked him if I could help him with the bar and he just flipped me off and said my hair was shitty,” Eijirou confessed before the two seemed to reel in the reality of their shared affections towards Katsuki.
It was confusing. The last four years were perfect. Without flaw. And now, despite both being at fault for the same feelings, they didn’t know what to think.
Was it cheating? Were they meant to get upset? Was it fair to Katsuki for the two to look lost in the midst of what was a cheating scandal gone.. right?
And with his age came the wisdom that some things, no matter how perfect they were, would shift into something more.
Katsuki knew that. The separation he’d gone through went similar. Well, perhaps not entirely the same given his husbands infidelity was not one of shared interest.
Katsuki was divorced because there was the other man. And so, the silence that went on despite knowing both men led him to feel that way.
As if he was the ‘other man’.
Katsuki felt stupid. He felt foreign in the space around him despite knowing the gym from the ground up. The race of his heart, something he’d felt in the past when Izuku left him, was back.
The worry that he’d ruined something, and not for the first time, was taking over every thought he was struggling to think through.
“I didn’t mean to cause problems. That was not my intention flirting with either of you. I had no clue that you were married. You don’t wear rings- either of you. And I.. I can’t imagine what you must be thinking so I’m going to go,” Katsuki explained, feeling childish despite being the oldest of the three.
He’d caused a divorce. Katsuki was sure he was bringing a relationship down before it could even transpire into the greatness it was meant to have. They were so young and new to the world around them. And he’d ruined it.
“Flirting?” Kirishima asked, eyes widening a bit as he gestured to Tetsu, “This idiot flirts by doing laundry. You flipped me off.”
“Wait, you were flirting?” Tetsu asked before his eyes looked over Katsuki’s build, biting at the bottom of his lip before looking to the redhead with a brow raised in thought.
Katsuki was sure he was seeing what could be explained as telepathy. The looks shared, eyes glancing without a word to be said. It was all so fast.
And yet he understood.
Yeah, Katsuki understood all too well.
“Yeah. We can do that.”
Eijirou wasn’t sure how Katsuki picked up on what they wanted. It wasn’t like Eijirou was sure of what Tetsu was really wanting himself, but the older man had agreed easily.
Almost as easy as it had been getting Katsuki’s clothes to fall to their bedroom floor.
The drive home wasn’t awkward. It wasn’t filled with the silence that Eijirou expected.
No.
The ride was rather laughter filled with Tetsu explaining what had to be the most embarrassing stories of their entire relationship.
Eijirou was thankful that Tetsu could occupy the thoughts that worked in his mind, but now the distraction was quite different.
The distraction now was none other than Katsuki spread on the bed. Eijirou and Tetsu’s shared bed. Katsuki’s back sat against the headboard with his carmine eyes focused on the two men working their way onto the bed.
Eijirou knew what Tetsu looks like on his knees. The redhead had seen those eyes between his legs many times. Just as Tetsu could picture how seductive Eijirou looks, eyes focused intensely on Katsuki rather than anywhere else.
Not like how Tetsu’s eyes would wander, focused more on the prize than the body attached to it. Or how Eijirou would mark the skin first, tease the skin around until he could settle where he was most desired.
It was hot to know each other so well that they knew what was going on. They knew how the other was reacting to the sight in front of them. And they had the picture of what would come. Of how things would play into their hands.
Almost.
Two palms came up to stop the men in their routine, mouths opened as if ready to play out what they desire most.
And Katsuki laughed. The man pushed his thumb into Tetsu’s mouth first without resistance, the tease on Kirishima’s plump lip leaving the redhead to open his own for the intrusion.
A similar confusion laced their expressions with narrowed eyes as the blonde slipped his knees between their naked thighs. Katsuki pressed his knees against their groins, cocks leaking precum onto his legs pitifully.
“It’s funny either of you thought you were in charge,” Katsuki teased, eyes working between the two men before he chuckled. “What? You guys sleep together all the time. I’m not a new toy.”
“I’m in charge here. And my handsome boys are going to learn a few things today.”
Katsuki worked his right leg carefully, working his knee against Tetsu’s cock as the silver haired mans eyes rolled back and his hips begin to roll into the touch. Katsuki begin to slow his movement, the hips rolling only working against the touch with soft groans gurgled by the thumb pressing against Tetsu’s tongue.
“Think you can be good too, Eijirou? Go ahead,” Katsuki encouraged, watching as Eijirou’s hips begin to roll in. The crease of the redhead’s brows deepened, sharp teeth tightening around the digit in his mouth.
“Good boys. Daddy’s good boys.”
Shared moans left the two with Katsuki’s compliment, hips working faster against him until each palm cupped their face to pull them down.
Sitting in his lap were Eijirou and Tetsu, cocks grinding against his toned thighs as drool begin to slip from their lips. “Yeah. Daddy’s good puppies, hmm?” Katsuki asked, the hitch from Eijirou forcing his smirk to grow.
“What? You’re the puppy? What about Tetsu then, puppy? Be a good boy and tell Daddy what Tetsu is,” Katsuki ordered, thumb moved from his mouth to the cheek to hold Eijirous face as the redhead kept humping forward eagerly.
“Princess.. Tetsu’a princess.” Kirishima answered, eyes fluttering as his hands went to the wrist by his face. Katsuki knew what he wanted, finger slipping back into the willing mouth until he could lean his face forward. His tongue slipped out, licking the trail of drool that slipped down his palm.
“Tetsu is pretty, isn’t he?” Katsuki asked once he could lean back, Eijirou’s head eagerly nodding as eyes glanced to the silver haired man on his left.
Tetsu was panting, rushed breathing picked up on with every rise and fall of his chest. His eyes were glazed over, tears collected at the ducts.
“Look at how wet you are, princess.” Katsuki encouraged, thick tears beginning to slip along Tetsu’s cheeks as the man nodded. Katsuki only hummed, shaking his head as he inched forward.
“Not there, sweetheart,” he encouraged, the wet sounds against his thigh only growing as Tetsu cried out and threw his head back.
“Do you see that, puppy? See how wet he is? His little clit is so pretty. Pretty and useless.”
The blonde helped both of them to sit up, slipping his knees from under them before removing his fingers. Eijirou and Tetsu sat there patiently as if waiting for the next order.
“Suck me off, princess. I need you to get the princess ready, puppy. You’re not allowed to use your fingers,” Katsuki ordered, happy the two moved with no complaints as Tetsu leaned down, his ass up in the air as his tongue rolled around Katsuki’s tip of his cock.
Only after the first few licks could he wrap his lips around the head of the blonde’s cock, his stretched lips worked around with the flat of Katsuki’s thumb.
“Daddy’s princess is so pretty. Look at that face,” Katsuki encouraged, groaning when the mouth around his cock vibrated with a moan.
One look up confirmed his thoughts as Eijirous tongue stuck out and lapped at his husbands hole. The mouth around Katsuki’s cock became wet, spit slipping down the rest of his length before his hand settled in the silver hair.
“Take it, princess. Be good for Daddy,” was all it took before the mouth dropped lower, gagging around the entire length as the hand tightened and the palm kept Tetsu’s face pressed against the mans groin.
The tongue lapping at his hole was eager enough for Tetsu’s moans to grow into cries of pleasure, legs wide to assure his husband had the space as Eijirou’s tongue worked along his balls before the pressure was back.
“You can open him up with your fingers now, puppy. Get the princess nice and wet for me,” Katsuki commanded, fingers finding way inside of Tetsu a moment later before the body under Tetsu was shifting.
Katsuki’s legs raised in the air lightly, hole exposed for the silver haired man sandwiched between them. “Go ahead, princess. Get me nice and wet for your husband, will you?”
Stretching didn’t take half as long as Eijirou thought it would. He was eagerly working three fingers inside of Tetsu’s hole when his eyes could finally look up to the sight ahead only to let out a whine.
Tetsu’s fingers were working inside of Katsuki’s hole, the older mans head thrown back in pleasure. His husbands mouth was wrapped around Katsuki’s cock, every inch down Tetsu’s throat as the hand stuck in T’s hair kept the man forced there.
A tug brought Tetsu’s head up, gasps for breath following as his husbands spit covered lips connected in a line to the head of Katsuki’s cock.
“Puppy?” Katsuki spoke, Kirishima’s attention finally focused on the blonde as the man smirked. “Back up, boy.”
The change of position put Tetsu on his back, Katsuki’s back facing Kirishima as the redhead awaited his turn.
The sharp hiss of his lover forced his knees to move, peeking at the sight of Katsuki’s thick cock splitting the man open.
“Fuck, princess. So wet.. so tight,” Katsuki growled, huffing as he could push inside. “Thank your puppy, sweetheart. Tell him thank you.”
“T’ank ‘ou, p’uhpy,” came a response, choked words forced from Tetsu’s mouth as the others legs trembled under the thrusts he was given to adjust to Katsuki’s size.
“Good boy. Such a good princess for Daddy. You ready, puppy?” came a question, the blonde leaned down enough to show his sloppy hole for the redhead with a smirk.
“C’mon boy. Fuck Daddy’s hole for me.”
The redhead lined up and pressed in, cock hitting deep inside as the man groaned and begin to work his hips. Rushed thrusts forced Katsuki’s hips to fuck just as quick, Tetsu’s eyes rolled back as his back arched from the bed.
“Fuck.. oh fuck,” Kirishima panted, arms around the blonde as his teeth sank into the others shoulder.
Bakugou could take the weight easily, comfortable with the extra weight as his own hips pounded into the man below. Katsuki’s hands helped Tetsu’s legs spread, feet high in the air as the wet squelching was quietened thanks to their shared moans and groans.
“Fucking pussy is so wet. Oh fuck, Eijirou.. right there, puppy. G-Goddamn,” Katsuki groaned, mouth dropped open as his palms hiked Tetsu’s legs to his shoulders and his cock nailed into the male’s prostate in return.
“Fuuck Daddy,” Tetsu whined, high pitched as his eyes rolled and his cock shot his release on his chest, release hitting his chin with thick spurts of cum.
The tightened hole under Katsuki forced his hips to still, the pounding from behind offering the warmth of release deep inside as his own orgasm hit. Eijirou grunted behind Katsuki, the sharp whines under him mixed in forced the blonde to shudder with overwhelming pleasure.
Katsuki was the first to collapse thanks to Eijirou’s weight, cock slipping from Tetsu’s hole as the others legs could find way to the bed. Eijirou’s cock slipped, immediately back inside the older man as the last few thrusts worked the leaking release from Katsuki’s hole back inside.
The redhead joined the two after another thrust, pulling out with shuddering breaths as his back hit the bed. Katsuki’s chest slipped into the space between the two, occupying the middle of the bed as all three caught their breaths.
“That was the best sex I’ve ever had,” Kirishima began, Tetsu interrupting with a groan, “Best sex /we/ have ever had.”
Katsuki just chuckled, rolling to his back carefully only to smile when two bodies immediately curled into his chest. “All had,” the blonde corrected, soft hums of agreement coming from the two on his chest.
“What would you think about being included in the relationship?” Kirishima asked, the first to open his mouth in the silence of the aftermath.
Katsuki knew it was for him, but part of him waited for Tetsu to speak out. For the man to speak against the offer.
Nothing came though which left Katsuki to open his eyes, shift enough that the other two raised from his chest to look at him. The men had their fingers intertwined as their faces held the same soft expression.
As if they knew something he didn’t. Which he supposed they did.
And Katsuki figured he had just a little more to learn before he could get as good at reading the two men as well as they read one another.
He was not the ‘other man’ but a third.
A third in what was meant to be an unbreakable bond. A third to strengthen the space in which Eijirou and Tetsu didn’t know needed to be filled.
“I would like that.”