Before taking the injection that bound his mind to Tony's, Steve had no idea how often Tony became almost painfully bored during the course of an ordinary, uninterrupted-by-supervillains, day. Having the running commentary of Tony's thoughts playing in his mind has given Steve a deep awareness that Tony's personality is tuned for a fast-paced, challenging, complex life.
Meetings, inspections, contract bids, conference calls, and a hundred other essential corporate details do not qualify.
This meant that Steve has acquired a lot of experience with how Tony prevents himself from expiring of sheer boredom and impatience. There are two ways. The first is by mentally designing tech. Technical specifications have become white noise by this point. The second is by teasing Steve with the most graphic, raunchy dirty talk Steve has ever heard.
Physical sensation doesn't come through the bond unless they're actually touching, but the pictures Tony paints in Steve's thoughts makes him feel like it does. Steve has had to lock himself in more than one washroom to relieve his excitement, sprawled on the toilet seat or leaning against the wall, hand jerking on his cock, a discarded glove shoved into his mouth to muffle his moans, and Tony's voice in his mind.
But today Steve hadn't been at lunch with a friend or meeting with SHIELD or working on his art. Today he'd been training with the other Avengers, one session after another, partly because they'd all had time today and partly because if he starts with Luke and finishes with Logan, Steve gets a pretty good workout himself. But the lack of breaks had meant that he couldn't relieve the tension, and on top of that he'd had to keep a tight grip on his control to keep from getting hard.
By the time Steve finished sparring with Logan the commentary had trailed off into coffee related thoughts, which told Steve where to find Tony. He stalked into the kitchen and Tony looked up with a smirk. "You seem a little--" Tony broke off with a squawk when Steve seized his upper arm and dragged him out of the kitchen. "Steve?" Tony asked, and he really had no right to sound that confused, not after what he'd been doing to Steve.
Steve doesn't answer, just hauls Tony into their room and shoves him at the bed. Steve has his t-shirt and sweatpants off almost before the door clicks shut behind them. Tony, leaning back on the bed, his legs spread in a way that pulls the fabric tight enough to show the outline of his cock, looks more amused than anything else. "In a hurry?"
Instead of answering Steve leaned over the bed and proceeded to strip Tony with efficient motions, moving Tony's body with his hands when Tony didn't cooperate fast enough. Barely two minutes had passed and Tony was only half hard when Steve pushed slick fingers into his body and curved them, stroking hard over Tony's prostate.
"Oh fuck," Tony gasped, body arching with sensation, and he was getting hard pretty damn fast now.
Steve worked him open with short, twisting thrusts of his fingers, eyes fixed on Tony's face, watching the spasms of pleasure that show there to distract himself from the heavy throb of his own cock. Tony whimpered, drawing a broken noise from Steve. He pulled his fingers out of Tony and replaced them with his cock in one hard thrust that tore a sob of sheer relief from his throat.
Steve gripped Tony's legs firmly, holding them open the way he needed them, and pounded into Tony's ass with short, frantic motions. The smack of skin on skin was loud in a room silent but for Steve's grunts of effort and Tony's startled-sounding cries of ecstasy.
It was over far too quickly. Steve came with a guttural moan, come spurting from his cock in a string of long pulses that gave his last few thrusts a wet sound. It was all he could do to remember to finish Tony off before collapsing onto the bed next to him, loose-limbed and relaxed at last.
"I really wish you wouldn't tease me like that," Steve said, stretching his arms over his head.
Tony just hummed absently and reached between his legs to rub at tender, sticky skin.