Bruce has cleared out a corner of his lab for Loki’s use. It’s covered in papers and books and a whiteboard has been removed from its stand and propped up against the wall so Loki can reach more of it. The overall effect is sort of like if Indiana Jones and Richard Feynman decided to collaborate on a project and then shrunk halfway through.
Clint and Bruce stand by the doorway and watch Loki work.
“Do you understand any of that?” Clint asks.
Bruce snorts. “Sometimes he asks me some physics questions, and those I get. How it all works with the magical theory he seems to be pulling out of thin air is anyone’s guess.”
“Here’s hoping?” Clint says dubiously.
“I got him to take a few breaks and have a snack,” Bruce says, shrugging. “Otherwise he’s been pretty hardcore. He hasn’t said much about what he’s figured out but he did say that he doesn’t like the feel of whoever made the device.”
They trade foreboding looks.
“How did you get him to take breaks?” Clint asks, impressed despite himself.
Bruce looks embarrassed. “I showed him some funny cat videos on YouTube.”
Clint grins. “Had those bookmarked, did you?”
“The Hulk likes them,” Bruce sulks.
Across the room, Loki steps back from his whiteboard, looks it over carefully, and then announces “I think I have it.”
“What, seriously?” Bruce says, startled.
“Way to go, kiddo!” Clint cheers.
“Yes.” Loki climbs over a stack of books and comes over. He’s got whiteboard ink on his new hoodie (which Clint is in no way happy about because he’s an adult and above such things), his hair is sticking up in odd places and he looks like a tiny absent-minded professor. Clint comes thisclose to making an extremely emasculating noise or, worse, telling Loki how adorable he is.
“Well,” Loki amends, “To be more precise, I think I have figured out the most basic form of the spell that changed us all, and I hope to be able to combine it with the energy from the device to be able to reverse everyone’s transformation. That everyone has changed differently makes it more complex and I think I will have to do one person at a time, but yes. I think I have it.” He beams up at them.
“Loki, that’s awesome!” Clint says. “Gimme five!”
There follows an interlude in which this phrase and its cultural connotations are explained, and then Loki dutifully gives him five.
“I just have to test it and then I will be ready to turn everyone back,” Loki explains.
“Great,” Bruce says. “What kind of test?”
“Well,” Loki says thoughtfully, “It is far easier to perform transformative magic on oneself than on another, so for the first attempt it is best if I try it on myself.”
“What?” Clint demands.
“Oh, Loki, I don’t think that’s such a good idea - “
“Nonsense,” Loki says brightly. “I assure you, this is the most practical course.”
“No, Loki - “
“Don’t - “
Loki’s face screws up in concentration. The air around him goes wiggly and warped, like he’s putting off heat. Clint shoves Bruce behind him and gropes for a weapon. They are so ludicrously unprepared to fight off a grownup Loki it’s not even funny.
There’s a sort of whumph feeling, and then Loki’s standing in front of them.
As a girl.
“Yes!” Loki whoops, doing a dance of victory. “I am a girl! Yes! It worked, it worked!”
Clint just stares at him, trying to perform the jarring mental shift from fight-or-flight to congratulations.
“That.. was not what I expected,” Bruce says faintly, clinging to Clint’s shoulder.
“No,” Clint agrees. Unlike girl-Tony, girl-Loki comes with long hair. Girl-Loki is thrilled.
“Look at my hair, I am the best ever!” She bounces up to them. “Am I a pretty girl?”
“Well,” Clint says slowly, “At that age I’d say you’re more ‘adorable’ than ‘pretty’, but I think when you’re grown up you’ll be quite a looker?”
“Huzzah!” Loki runs over to one of Bruce’s glass-fronted equipment cabinets to admire herself. “Oh, I am quite cute. I have always wanted to try this spell, you know.”
Bruce's hand spasms on Clint’s shoulder. “Then we’re even more proud of you,” he says fiercely.
Loki twirls in front of the cabinet. “I like being a girl,” she decides. “After I fix everyone, may I try it again?”
“Sure thing,” Clint says. “Does this mean you’ll try fixing Tony first?”
Loki nods seriously. “He will be the simplest, so it is best to do him first. Then I think you and Natasha may be switched back. I am unsure as of yet whether it will be easier at that point to revive Thor or to restore Steve.” Her face screws up again, and then with a nausea-inducing warp of reality he’s back as a boy. He staggers, suddenly pale.
“Oh,” he says sheepishly. “That took a little more energy than I expected.”
Clint scoops him up. “We’ll get some lunch and then you can rest a little, how’s that? Maybe this afternoon we can sort Tony out.”
Loki nods and rests his head against Clint’s cheek. “I totally turned into a girl,” he says smugly.
Clint laughs. “Yeah, you did,” he says.