Prompt:

"One of the popular trends in the 1940s is the Siren Suit. It was made popular by Churchill because it was warm and practical.
One day, Steve discovered that a modern version of this exists called the 'Onesie'. He decided that he loves it and wears it every chance he gets.
Cue the Avengers and the media reacting to it in different ways.
Bonus: Have Steve carry a blanket while wearing a onesie."

"Captain Onesie"

The first thing that happened when Steve walked into the kitchen was a simultaneous spit-take from Tony and Clint. Natasha raised both eyebrows, Bruce rubbed his eyes, and Thor merely kept on beaming. Steve smiled back, though it dimmed a little when he noticed that the others were all just staring at him. He looked down at his clothes, and then back up.

"What?" he said.

"You… wore that to bed?" Natasha asked.

"No."

"To the gym?" He shook his head. "Or running?"

"No," he repeated. "I wore it to the shops. We were out of staples." He held up the bag of shopping in his left hand, and placed it on the counter. Thor immediately dived in to fish out the new box of pop tarts, and started putting everything else away while Tony chugged down water and Clint drank juice.

"Too tired for this," Bruce muttered. "Tony, could you move?" Tony coughed again, and shifted away from the coffee-maker. "Thanks."

"What's wrong?" Steve said. "The lady at the shop said it looks swell."

He was referring to his chosen outfit for the day. It was a candy-striped onesie, an all-in-one ensemble, complete with hood, lined with fleece, and sturdy shoe-like soles. He didn't wear it for exercise, of course. But as casual wear, it was comfortable, warm, and it reminded him of the past.

"Churchill wore siren suits, and these are the same kind of thing," he continued. "Just… more colourful."

"They sure are," Clint said, voice still hoarse. Steve cocked his head.

"I've seen lots of people wearing them," he said. 'Lots' was a bit of an exaggeration; but enough people were wearing onesies for it to be in fashion. "I like them." An understatement. "I bought… a couple of dozen of them." He blushed when a few jaws dropped. "Not a problem, is it?"

"You can wear whatever you want," Natasha said, her face more inscrutable than ever.

"Holy crap!" Tony said. Bruce jumped, and Clint rubbed the bridge of his nose. At some point, Tony had got onto his phone, and was staring at it, wide-eyed. "He's trending."

"Well, these are trendy," Steve said, indicating his clothes. Thor was the only one who laughed at his joke. "What's trending?"

"You," Tony said, and shoved the screen in front of Steve's nose. He nearly went cross-eyed trying to read it.

"Captain Onesie," he said.

"It's a hash-tag," Tony said. "There are pictures. Steve, you're Captain Onesie! Oh, this is gold."

"Expect a visit from SHIELD," Clint said. "God, I can't wait to see Coulson's face when he sees you in one of these, up close and personal."

Steve blushed again.

Because this is Phil Coulson's life, he was relegated the job of tracking #captainonesie on all of the social media websites. Twitter, Tumblr; monitoring the Facebook page which had been set up within an hour of the first Instagram. For five hours, he trawled the internet. After Romanov told him to check out his TV, he switched on to the news and saw the tag running along the bottom of the screen. As he watched, there was a fifteen-second report on Captain America in his onesie.

"Oh God," Phil mumbled, and he buried his head in his hands.

SHIELD did not have a contingency plan for this.

Then an email arrived from Barton, with about twenty attachments. Phil flicked through the slideshow, all pictures of Rogers' new clothes. Phil deleted the email and its contents, wishing he had some way to delete the memories from his brain. But if Rogers intended to wear all of these outfits, Phil would see pictures of it sooner or later.

And… God, people were already photo-shopping. And how does someone manage to end up with three Facebook fan pages, a Tumblr, and a fan club within six hours of wearing a onesie out in public? If this was an example of his coming days, Phil was going to be busy, probably for the rest of his career. And he'd need to delegate, if he read the situation correctly.

Unless he could do damage control…?

Regardless, it seemed like Phil would have to witness the phenomenon for himself, first-hand.

Steve had to start taking different routes out of Stark Tower and to the shops. He noticed more and more people wearing onesies, sometimes the same one he wore the previous day. He became the unofficial face of every onesie manufacturer. When one of the major companies started a superhero line, Steve was asked to cut the ribbon at the official opening. He surprised everyone by turning up in a tuxedo onesie.

That was where he saw Phil.

"Agent Coulson," Steve said brightly, and he walked over to the agent. "I heard you were handling the fan mail."

"In a manner of speaking," Phil muttered. He eyed Steve up and down. "How did… why did you start…"

"I saw someone wearing one, and thought they were just out in their pyjamas," Steve said. "But then I was in a department store, and saw them with ordinary clothes. Then I started to see more people wearing them. They reminded me of one of the fashions back in my day. I looked it up on the internet, and found out what these are called." He indicated his outfit. "So I tried one on, and… sort of fell in love with it." He blushed. "And it kind of went down hill from there."

"I see," Phil said.

"Do you… think it looks ridiculous?"

There was a pause. Then, "You make it work."

"Well, that's diplomatic of you," Steve said, fighting a twinge of hurt. "Why're so many people hung up on this?"

"It's very… unexpected, Captain. That's all. It's a growing trend. Thanks to you, it's catching on like wildfire now."

"Good thing or bad thing?"

"When it's you wearing it?" Phil said. He smiled softly. "Good thing."

When he got back to his office at SHIELD, Phil's view on the matter wavered.

"Damn it," he said, scrolling over the pictures.

A few people had taken snaps of Phil and Steve talking, and #agentcoulson was now a tag. Some had photo-shopped a onesie onto Phil, and more images kept appearing, including drawings where Steve's blush was emphasised. Phil got onto the phone.

"I've been compromised," he grumbled to the technician on the other end. "Get rid of those pictures now, and any hint of the Agent Coulson hash tag." Then he hung up. "If we can't censor the internet, no one can."

By the afternoon, photos were still getting on to Tumblr, Phil had his own Facebook fan page, and people were starting to 'ship' him with Steve. All of this could only end in disaster, as he pointed out in a video conference with the Avengers. They just laughed.

"Stark, if I find out that you're blocking our techs from taking down these images, I will castrate you with a spoon," he said.

"Why a spoon, Agent?" Tony asked.

"It's blunt," Phil said. "It'll hurt more." Then he hung up, and thumped his head on the back of his chair repeatedly.

It was probably just as well that most of his enemies were either dead or incarcerated. At this rate, he wouldn't care if the others came after him, if it meant that he no longer had to deal with this problem.

The day Fury told Phil that eighty-five percent of SHIELD employees had requested Kevlar onesies was the first day Phil ever honest-to-God cried at work.

His day was just capped off – no pun intended – when he got back to the Avengers headquarters to witness Steve carrying a blanket into the common area for movie night, shuffling along in a teddy bear onesie with the hood up.

Phil would forever deny that he held onto the wall for support.

This was based on a prompt from the Avengers Assemble kink meme, round 21, page 69. Took me awhile to work out where I wanted to go with it. I tried so hard not to turn this into Capsicoul, but gosh darn it! Sigh. Calling it pre-slash, I suppose. I don't know. Who could resist Steve Rogers dressed as a teddy bear and carrying a blanket? Even I look adorable dressed as a teddy bear. (Long story.)

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