Work Text:
Dean knew he should tell Sam to do that in the bathroom. Especially since Sam had been trailing his hand over his own bulge all day. As far as Dean knew, Dad didn’t have a clue or he would have barked out an order about cleaning the pipes long ago. But Dean knew.
Dean knew the hitch in his brother’s voice from the back seat meant he was letting himself get too close. Dean knew from the little puff of air that burst from Sam’s lungs that he’d figured out how to cup himself during dinner. Dean knew that the slight flush in Sam’s cheeks had nothing to do with the warm day and everything to do with him pressing himself against the car while he filled it with gas. Dean knew the tip of Sam’s tongue sticking out of his wet lips was not in concentration of his school work, but in concentration of attempting to grab himself with one hand deep in his jeans pocket.
And now that the day was done, Dad snoring away in a whiskey induced slumber, Dean knew he should tell Sam to be more discrete. That he should excuse himself. That he shouldn’t be doing that with two other men in the room.
Instead he tried to still his breathing as he felt Sam shift in the bed next to him. Instead he tried to stop his own hand from seeking out his hardness as Sam’s arm started moving in earnest. Instead he tried to calm his heaving chest as Sam moaned lightly and curled in on himself, facing away from Dean.
Without his consent, Dean’s hand moved on its own into his boxers, shoving them down slightly. The first touch of his heated flesh made him gasp, making Sam freeze for a second. Dean forced himself to relax his muscles, to appear boneless and sleeping, so his brother would continue.
As Dean waited for Sam to resume his activity he stroked himself agonizingly slowly so he wouldn’t draw attention to himself. Dean felt the heat build alarmingly fast in his lower belly as Sam started moving his hips again. The soft little noises Sam was trying to hide floated across the bed and slipped between Dean’s hand and his cock.
Dean breathed through his mouth in an effort to be silent as Sam’s breathing became ragged next to him. Dean’s hips moved with a mind of their own, bucking and rutting gently as Sam picked up his pace. Dean heard the wet sound of Sam smearing his precome up and down his shaft. Dean felt the bed bounce as Sam shifted so he was on his belly, propped up on one forearm. He heard the sound of the sheet sliding as Sam drew his knees up and lifted off the bed slightly.
Dean risked a look over to see Sam’s lips parted, mewling around his pretty tongue. He desperately wanted to spread his legs wide, get a finger inside himself, moan and snap his hips up into his fist at the sight. Instead he tried to slow his movements so he wouldn’t be caught watching Sam. Dean closed his eyes as he slithered his other hand until he was stroking his nipples, listening to the soft sheet slip on Sam’s ass, the wet sound of Sam’s palm stroking his cock, the breathy moans that kept falling out of his mouth.
When Sam’s breath hitched Dean almost lost it. Dean could feel Sam’s muscles tense next to him. He could hear Sam’s hand working faster. He could imagine the hot pulses as Sam gasped and shuddered next to him.
Dean froze. He knew he should be more discrete. He knew that he shouldn’t have his hand wrapped around himself while sleeping next to his brother. He knew he should get up and go to the bathroom. Instead he grabbed himself a little harder while Sam’s breathing slowed. He pinched himself more as Sam fussed with something between himself and the bed. He bit off a moan as he heard Sam’s underwear snap back into place. He leaked all over his stomach as he tried to hold the explosion back as Sam shifted again.
“Here, use this,” Sam ordered in a low voice. Dean’s eyes snapped open in time to see Sam flick the sheet away from him and place a slightly sticky towel on top of his pelvis. Sam’s eyes met his as his orgasm rushed to the surface and he emptied himself into the towel, adding to Sam’s mess. He barely held back the whimpers from the back of his throat as he stroked every last drop out. When his hand stilled, Sam took the towel back and dropped it on the floor.
Dean quickly pulled his boxers back into place while Sam put one finger in front of his shining lips in a silent ‘shhh’ and a glance to the other bed. Dean noted that Dad’s snores had stopped but his breathing was still even. Sam put the sheet back on top of Dean, tucking him in like a kind lover, and ghosted his lips over Dean’s forehead before settling down to sleep.
It was a very long time before Dean followed his brother into sleep.