AN: Based off this awesome AU masterpost I found on Tumblr, which had a list of suggestions for different kinds of AU scenarios (also inspired chapter 23).
Don't Need a Halo
One hand buried in Tafari's mane, Clint tilts his head and scrutinises the man sat in front of him. "You don't look like an angel."
Bucky laughs. "What do angels look like then, kid?"
He thinks hard, trying to remember the one his mother used to lift him up for so he could put it on top of the tree. "They're girls," he says, "and they have yellow hair and gold dresses and wings."
Sighing, his friend nods. "I don't have much of that, do I?"
Clint shakes his head, moving his hand around Tafari's mane to give the lion something to purr about; ever since Barney dared him, Clint loves to pet the big cat when the older circus people get mad at him. He knows he should probably be more careful, that Tafari could turn on him in an instant, but ever since Bucky showed up he's been feeling a bit braver. Bucky's the nicest adult he's ever met. After his mom.
"What's the most angel-like out of all those things?" Bucky asks again, and Clint answers without hesitation.
"Wings."
"So if I had wings, would you believe that I'm an angel?"
Nodding, Clint watches as Bucky grins excitedly, standing up and moving into the centre of the animals' tent. He stands still, flashing Clint a quick wink before closing his eyes.
Tafari suddenly stands up, padding over to the corner of his cage and sitting down, gaze directed at Bucky. Confused, Clint notices all the animals have done that, and a double-take at Bucky reveals why: shifting to his knees, Clint stares open-mouthed at the faint smears of light extending from Bucky's shoulders. They're bright in the way the sun trying to burn through a foggy sky is, a distant warmth emanating from them, and he thinks if he could touch them and they'd be soft, smooth, strong…
"You have wings," he gasps when the lights disappear and Bucky is sitting across from him again. His face splits into a grin. "You're an angel!"
"Not just any angel, Clint," Bucky says gently. "I'm yours. Your guardian angel."
The seven-nearly-eight-year-old doesn't immediately process that. It's only after he remembers his mother telling him a story while Barney was at the hospital, assuring her son that regardless of what their father did there was always an angel watching them ("I swear on my grave I'll find a way to watch over at least one of you,"), that he realises what Bucky means.
Bucky holds Clint until he cries himself to sleep against his chest, two arcs of gentle light encircling the child in his arms. He promised Edith out of kindness, but now he knows he'll do anything to keep the boy from coming to harm. Anything. From behind the bars, Tafari rumbles his assent.
AN: Prompt: "Oh my god ay of the AUs please theyre all amazing Maybe just, winterhawk? That'd be nice"
Saw 'fallen angel AU' in the masterpost and altered it slightly... I like this idea though. May run with it again one day!