Tony is the hardest to swallow.
Steve finds it strange, really. So many people died that first day in the early morning hours in their sleep, having never left their beds, having never heard that terrible warning. Countless friends, families, coworkers, fellow agents and heroes. Millions to billions of people never stood a chance when sleep became instantly fatal at precisely 4:06 AM EST. Natasha and Clint, still snuggled up against one another in one final, fatal embrace. Pepper, curled about her pillow and hugging it tightly to her chest. So many deaths. Even Sam, who had groaned when Steve tried to wake him for an early morning jog about the park at 4:00 on the dot, rolled back over, and burrowed under the covers to ignore him for another ten minutes. They are all somehow easier to take than Tony.
Tony, out of all of the Avengers, is the only one who survived the initial onset of what the inventor dubbed ‘the Big Sleep’ outside of Steve. He had been in the lab, working on who knows what after who knows how many hours awake, when Jarvis alerted the inventor to the events unfolding just outside the Tower and within the Tower.
Tony had fruitlessly spent the first day sobbing over Pepper before throwing himself headfirst into attacking the problem at hand. It was rather like the inventor aimed to take revenge on the Big Sleep any way possible. Steve did not blame him. Instead, Steve helped wherever possible, mindful of the fact that his enhanced body would likely last much longer than Tony’s without sleep.
When Tony flagged, Steve had been there. He had been there with sugary snacks, with coffee, with energy drinks. Eventually, Steve had even been there with adrenaline, biting his lip as he stabbed it into Tony’s chest and murmuring countless apologies afterwards when Tony jerked awake - alive - and rubbed the injection site. Steve had helped Tony to steady his hands when the tremors came in the wake of the drugs and after when their efficacy began to dwindle. Steve had even been there when Tony had resorted to the sanctuary of the suit, all the times when Jarvis had been forced to shock Tony awake.
Steve had been there when Tony eventually succumbed and fell asleep in the early morning hours of day five – too swiftly and too deeply for Jarvis to rouse or revive him. Somehow, that has hit Steve harder than any of the others. A part of him thinks it may be because Tony slipped away in his hands. Another part of him wonders if it is because Tony was the last person left to his knowledge.
Losing Tony has taken a great toll on Steve. Before Tony, it had not been too difficult for Steve to stay awake, to stay positive. Tony’s spirit had been an infectious thing, buoying up Steve’s will. Now that Tony is not there, Steve feels so very tired. He knows it is his grief dragging him down, but that does not change a damned thing.
He cannot stay in the Tower, not with them. No. Steve knows he must leave before he loses his mind or any more of his will to stay awake and stay alive. Steve packs what he needs in a backpack, or at least what he thinks he needs. He takes his shield as well but leaves the suit.
Jarvis strangely, speaks to Steve as he strides through the lobby of Stark Tower towards the street. “Mr. Rogers?”
When the artificial intelligence speaks, it sounds acutely sorrowed in a way that surprises Steve. “Be careful, Mr. Rogers. And good luck.”
Steve pauses and nods solemnly. “You, too, Jarvis.”
“The arc reactor at the Tower’s core is relatively self-sustaining. Barring any unforeseeable events, I will be here.” Jarvis does not say it, but Steve hears the offer, the plea there.
And, then, he leaves the Tower.
For many hours, Steve wanders the city. It is entirely eerie to hear New York City so silent and still. It is as though the entire city has become a tomb. He walks and listens, hoping for any sign of life anywhere. His heart hammers in his ears as Steve begins to worry that he is, perhaps, the last man awake and alive.
Worse, when Steve listens closer, there is nothing. There is not a sound. No birds. No pigeons. No dogs. Nothing. His stomach turns to realize that the animals are dead, too. Everything. Everything in the world is gone save him.
Panic takes Steve then quite abruptly, and he bolts. Steve runs. He goes as fast and as far as his legs will take him. He darts down the abandoned, empty city streets, every vacant building only furthering his fear. His flight is mindless in a way, with no clear direction or plan. He loses himself in the feel of his long, powerful strides.
He does not know where he can run to, if nowhere is safe from sleep.