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Casey heard the last door of Squad's rig slam and winced. He ran a hand through his sweaty hair and sighed. It had been the kind of call they all dreaded; no happy ending, just human misery and hard work. Severide had had it the worst, watching the save slip through his fingers from a front row seat.
Everyone was drifting into the common area and the showers to do their own version of processing the stress. Otis surfed eBay, Cruz played video games until his vision blurred, Hermann flicked through pictures of his kids on his phone and told anyone who would listen about their latest pranks and achievements.
For Severide it varied. He could never sit still after the ones that didn't go the way they wanted. Most often something else managed catch his attention, or he'd take squad on a ride. Other times he snapped at everyone and found some really shitty life choices to make.
Right then he was shrugging off Capp and Cruz's efforts at comfort. It looked like he was taking it hard and it reminded Casey in the worst way of what he'd been like after Darden's death. Back then he'd been hiding an injury and in near constant pain. Casey's anxiety spiked and he headed over despite the obvious storm brewing.
"Severide, you need Brett to check you out?"
"No," he carried on walking and Casey shouted after him.
"You sure?"
Severide's head swung round and he gave Matt a disbelieving look before striding over and trying to tower over him despite them being basically the same height.
"Yes, Captain," he mocked. "Now get out of my face."
Casey bit down on an angry retort and glanced around. They were alone on the floor and he took the opportunity to grab Severide's collar and herd him into the kit room.
He couldn't help running a hand down Kelly's back once they were inside unsubtly searching for injuries. They were careful about their interactions these days but Matt was worried and he didn't trust Kelly to tell the truth right then.
"Get off," muttered Severide, shrugging him away and crossing his arms across his chest defensively.
Casey glowered back at him. God he was irritating when he got like this. Why couldn't he just find a way to process or talk about his feelings like a goddamn adult? Severide quickly got tired of the stand off, fidgeting and looking like he wanted to pace, or possibly punch something.
"What is it, Casey? I've got shit to do."
Matt took a slow breath and tried to focus, he was meant to be calming Kelly down, checking in, making sure he didn't make any of those really shitty decisions he loved so much in these situations.
"The call..," he started, uncertain how to handle it. "This isn't on you, Severide. There's nothing more you could have done."
"Don't you think I know that?" Kelly said, jerking up from his slouch against the wire cage and stalking over. "Just because we're fucking now doesn’t mean I'm gonna go pouring my heart out to you every five seconds."
Casey took a step back in surprise. He knew Kelly lashed out when he was in pain; had been a recipient of it often enough but it hadn't happened since they'd started whatever this was between them. It had a different flavour now somehow.
They might not have really talked through their feelings but it was all very real, or it was to Matt at least. He felt like he'd been sucker punched and it must have shown on his face because Kelly stepped back and stared at him, anger warring with half a dozen other emotions on his face. Casey sucked in a breath to say something, pictured the argument and turned to leave instead. He wasn't sure what he'd been thinking, he and Kelly only ever seemed to make each other's tempers worse.
"Matt," Severide's voice cracked behind him and Casey felt a hand on his shoulder. "I can't…," he trailed off, voice raw. "You're right, I'm spiralling I don't know how to stop."
Matt hesitated and then moved away letting the hand slide off, Kelly made a frustrated sound behind him. Walking to the door he turned the lock and stood with his hand on the knob.
"I'm gonna try something, Kelly. You can tell me to stop any time."
Severide needed a distraction, a way to calm his churning thoughts, distance himself from the vicarious grief, and to burn through the rest of the adrenaline. He wasn't the only one, Casey could feel his own veins thrumming with frustrated energy. Truck hadn't even had the chance to move in, the blaze had been too far advanced.
Kelly frowned back at him and then gave him a confused and jerky nod. Heat ran through Matt, he couldn't believe he was going to do this.
"Get on your knees."
Severide's eyes widened in surprise.
"Case, we said…," he started but Matt cut him off.
"That's an order, Lieutenant. From your Captain." He made sure his tone was the one he used when he gave orders to 81, nothing like when he and Severide were alone together. Nerves warred with arousal, this could be a disaster but if it wasn't...
Moving forward he stepped into Severide's personal space, getting in his face and backing him up against the wall.
Severide wavered, wide eyes flicking over Matt's face. For a long moment Casey thought he'd just brush it off and leave but then he slowly sank down.
There wasn't quite enough space to do it gracefully but Matt didn't move back. He let Severide struggle to fit his knees around his feet, already straddling one thigh and trapped in the small gap between his Captain and the wall. Matt's blood felt molten.
"Case," Severide breathed, bringing his hands up to rest on the thick fabric of Casey's uniform pants, his pupils already blown.
Matt let his hand drop and cupped Kelly's jaw, imagining how far he could take this. He rubbed a thumb across Severide's lower lip and pressed down, slipping it inside the heat of his mouth. Severide sucked in a breath and swirled his tongue around the digit. It was confirmation enough for Casey that this wasn't a terrible idea, that he wasn't the only one already unbearably turned on. And as he'd hoped, Severide's body had gone still and all his attention was focused on Matt, no longer mired in self doubt and second guessing himself.
He used the grip on Kelly's jaw to tilt his head back until it knocked gently against the wall. Ordering his hands not to shake he brought them to his belt, popped the button and unzipped his fly slowly. Severide's eyes flicked between his face and his crotch and his tongue darted out instinctively.
"Captain."
"Shut up," Casey paused and pushed his boxers down pulling his cock out, "Lieutenant."
Severide's eyes closed for a moment on a whine.
Casey let the tip of his cock rest against Kelly's lower lip and smeared it across. Severide groaned and opened his mouth to take him inside but Casey used a hand on his face to hold him still, keeping his head resting back against the wall.
Severide's breath came faster and he squirmed, moving his hands around to rest on the back of Casey's thighs urging him forwards.
"Please."
Matt shifted forward pushing inside Kelly's mouth agonisingly slowly. God it felt good, Kelly hummed in pleasure and his tongue slid around Matt in welcome. He fucked in and out shallowly for a while, enjoying the feel of it and letting Severide grow accustomed to the angle.
It wasn't long before he felt fingers digging into the back of his thighs and he smirked down at Kelly.
"Trying to get me to fuck your face, Severide?"
Not giving Kelly a chance to respond, he pushed forward bracing one palm against the wall and keeping the other on Kelly's cheek. He felt himself reach the back of Severide's mouth and trigger the gag reflex but kept going, moaning softly as he felt the muscles clamp down around him. Fuck he needed to remember they were at work. This had to stay quiet.
He held still for a second and then pulled back letting Kelly pull in a shaky breath. His eyes were hazy with pleasure.
"Yes?"
"Yes," Severide breathed. "More."
Lust swept through him, it was a rush to have Severide staring up at him this way, lips wet and utterly in his hands. He gave in to the need to be back inside him and pushed into his mouth without hesitation letting his cock slide all the way to the back of Kelly's mouth and further. This time Severide managed to relax around him better and his eyes slid shut.
Casey leaned forward and started moving in earnest. He kept a hold on Kelly, thumb digging into his jaw and fingers wrapped around the back of his neck not allowing him to move and he slid in and out. Every so often Kelly would gag, tears leaking from his eyes and he eased off to let him take a breath but Severide's grip on the back of his leg always drew him quickly back.
As Casey looked down he heard the slide of a zipper and realised Severide's right hand had slipped from his leg to grip his own cock. Confirming his suspicions, Kelly moaned louder and Casey thrust forward to try and shut him up.
"Fuck, you gonna come like this Sev, with my dick halfway done your throat?"
A broken noise of assent came from the man on his knees and Casey sped up making him choke again and then his face contorted, more tears slipping from eyes squeezed shut and moans rolling into one another.
Casey recognised that sound. Severide really had come like this and so fast. The thought of it nearly tipped him over the edge himself and it was only a couple more thrusts into Kelly's suddenly limp body before he came. He ground into Kelly's throat and barely had the presence of mind to pull back as soon as he finished coming before he really did choke him. Casey released Severide's jaw still gasping and leaned hard against the wall as his legs tried to give way.
Severide let his head fall forward so that his forehead pressed inside Casey's hip bone. Matt scrubbed a hand through the greying hair and let Kelly rest there for a second. When he finally pulled away Matt put his clothes back into order.
"Better?"
"Yeah," Kelly's voice was wrecked and triggered a surge of emotion that washed through Casey like a tidal wave.
Matt slid down and finally pulled him into a hug. Severide hung on like a drowning man for a second and then relaxed into the embrace.
"Thanks, Case," he mumbled into Matt's shoulder.
Casey pulled back and cradled Severide's face in his hands feeling rough stubble against his palms.
"Always." He looked into Kelly's reddened eyes and pressed a quick kiss to his mouth. "You don't have to carry everything alone."