Tony is down in the garage. He's been down there for at least two days. He'd lost track of time since Steve had left for the mission. Once Steve had left, that's when Tony had migrated to the garage. Hours and days passed as he worked.
He upgraded Dummy's software, patched Jarvis into the vehicles, tinkered with the armor, and found a myriad of ways to keep himself occupied. The numbers, equations, and physics kept his brain occupied and running at top speed. It seemed that every so often, when he'd stand and crack his back after hours hunched over one of the work benches, there'd be food sitting on one of the tables for him. It was probably Bruce or Pep's way of making sure he was okay. They knew he slept on the couch in the garage while Steve was gone, finding the bed in their room too big and cold without him in it, next to Tony, and keeping the nightmares at bay.
The couch was perfect for Tony; every time he took a nap on it, once the dreams started and he began thrashing in his sleep, he'd fall off the couch and wake up. That was his version of an alarm clock. Hit the concrete - back to work. Everyone else in the Tower knew but never commented on the Captain America blanket that he slept with on the couch and kept hidden away behind a pillow when it wasn't in use.
Steve found him that way when he came back from a four-day mission with Bucky. Tony was limp on the couch, curled up in the smallest ball that he could physically fold himself into. It looked as if Tony were protecting himself - or perhaps more accurately, the arc reactor. The blanket was wrapped around him and the corner of Steve's mouth quirked up in a small grin, thinking that Tony looked very much like an adorable burrito. The deep blue of the blanket was a stark contrast to his wildly messy hair and made the splotches of grease on his face stand out like the dark bruises that had appeared after the Battle of New York.
He watched Tony for a moment, taking in the slow and steady rise and fall of his side. A hand was curled under Tony's chin, like a child would. For all his bluster and self-built walls, Tony was incredibly vulnerable and Steve was beginning to realize as their relationship progressed, just how vulnerable Tony really was. It was most noticeable when he slept. Tony was defenseless and the arc reactor was open to any mercenary's greedy fingers in his dreams. Sometimes the specter took the form of Obie in Tony's dreams, Steve knew, and sometimes it was his father, saying Tony would never be good enough for him, that this life-saving creation - Tony's Mona Lisa - was a waste of energy and thought. It was only recently that Tony had begun to open up and share those dreams with Steve, as he came to trust the man more. Steve knew that it took a lot of courage for Tony to share those details with him, trusting him like that, giving Steve the chance to rip his heart out just like others had done before him.
With a sigh, Steve turned and began quietly cleaning some of the mess on Tony's workbench. It was mindless puttering, allowing him to downshift a gear in his brain and be able to sleep soon. He cleared away the plates of food and the scraps of paper and bits of metal that Tony had scrapped, letting the mission, the details, the long hours drain out of his mind. A quiet calm replaced the buzz of distracted thoughts leftover from the debriefing. A snort sounded over Steve's shoulder and he looked at Tony, finding that Tony had shifted slightly and was now snoring.
A smile - genuine, not strained from stress or worry - appeared on Steve's face, erasing the lines that the mission had wrought into it. Steve wondered when Tony had begun to be the source of laughter and joy in his life, when Tony had replaced the discombobulation of the new century, and when Tony had crept in and staked Steve's heart as his territory.
It was then that Steve found the drawing.
He had always known that Tony was gifted at drawing technical designs for his machinery and different creations. Tony had always waved Steve's questions away with a dismissive hand when Steve asked him if he'd ever pursued just drawing for artistic creativity and the ability to let the ideas flow. Steve had gotten the response that Tony would leave the arts to Steve (along with the fabulous pulling off of a certain spangly outfit) and Tony would just continue to draw when he needed to keep the lines and numbers straight outside of the plan in his head.
This drawing - this was different. It was still technical, but it had something to it, an undefinable element that brought warmth to the lines sketched in graphite. It was a band no more a quarter of an inch wide with a groove cut through the center all the way around the band. The band was deep too, standing a quarter of an inch tall. Steve wondered how long Tony had sketched this idea. Normally, Tony's drawings were done solely in graphite with notations on the page and equations on the back. This page had all of that, but Tony had found a light blue colored pencil and shaded the groove in the ring. Steve titled the paper, reading some of Tony's cramped handwriting.
It was then that Steve realized what Tony had been drawing.
To propose to him.
Steve's mouth hung open for a moment or two in shock as he stared at the drawing, his hands holding it reverently, as if it were the Holy Grail. To Steve, it was. This drawing told Steve everything he needed to know about Tony and then some. Tony wanted to make his relationship more solid and defined with Steve and Steve was willing to bet that it was Tony's abandonment issues that had pushed him to entertain this insane notion of marriage - which Tony avoided like the plague - in the first place. The fact that Tony had put exquisite effort and time into this drawing spoke of the heart behind the brain in the man of iron. Tony had wanted it to be meaningful and perfect for the two of them, down to the last minute detail.
According to Tony's notes, the band was made of vibranium - most likely the few scraps that would have been left after Howard had forged Steve's shield. The groove was to be filled with a small but functioning band of Antonium - the element that Tony had created to save his heart and replace the failing palladium cores only a few short years before. The ring was to be a perfect melding of the best of them. A representation of their better halves, their hearts, their souls in one unbreakable and beautiful physical metaphor.
Steve closed his mouth, a strange fluttering in the pit of his stomach. He carefully tucked the page away under a stack of papers, knowing that Tony would think he had shoved it there in his sleep deprivation before crashing on the couch. Steve wouldn't say a word about it to Tony, letting him decide when the time was right to ask Steve that all-important and nerve-wracking question. With a smile that reached his eyes, Steve knew in a solid, steady heartbeat what his answer would be. No, he would be patient and wait until Tony was comfortable enough with the idea of marriage to propose to Steve.
However, there was no harm in gently prodding him with jokes and hints about "the 'M' word", as Tony liked to call it. Steve chuckled and scooped up Tony in his arms, carrying him off to their bedroom for a real night's sleep. Tony sighed happily when Steve settled them both under the covers in their large bed and curled his long, warm body against Tony's still limp frame.
Steve wrapped one arm around Tony and nuzzled into Tony's neck before closing his eyes. He grinned as Tony rolled over in his sleep suddenly and turned into a mini-octopus, wrapping himself around every inch of Steve he could reach, the Captain America blanket tangled between their legs now.
Oh yes, there was definitely no harm in poking Tony about marriage, Steve decided as he closed his eyes happily and drifted into sleep. First on the list of jokes would be calling him "Mrs. Rogers" in the morning, just to see Tony's brow furrow and that early morning sass appear. Steve was going to enjoy the next few months - and the rest of forever with Tony, his mini-octopus, his partner, his heart.