A/N: Alright, so I filled a bunch of prompts on Tumblr a few weeks ago, and now I'm finally getting around to posting them on here.
Ironically, this one wasn't really a prompt; a friend of mine and I were talking about different headcanons we had about how Natasha got the Hulk to trust her, and this was the result. Enjoy!
Beam. On her leg.
Natasha's had better days. She's also had worse days, but lying three floors below ground in a partially-collapsed Hydra bunker with a ceiling beam crushing her leg is no party. She growls in frustration when she only gets static in her ear pierce.
"Let's attack an underground bunker, Steve said," she mutters. "It'll be fun, he said."
Not that she thought anything of it at the time. It had been just another mission: get in, cause chaos for Hydra, get out. The 'get in' part was easy enough. The 'get out'… not so much. She only had a moment's warning from Clint's shout over the comms before the place was crashing down around her.
A loud crash startles her briefly, before part of the rubble above her head is ripped away, revealing a pair of green eyes staring at her.
The Hulk blinks. Natasha blinks.
"Um…" she peers past him, unable to tell if he's come from the surface or been buried like her. There's no sunlight that she can see, but it's possible that she's just been buried that far. "You got a shovel?" she jokes.
The Hulk huffs. He backs away a bit, reaching through the hole he's made to carefully poke at her trapped leg.
Natasha winces. "That's okay. I'll just sit here until the others find us."
And she'll be adding this to the list of things she isn't expecting - the Hulk gives her this look. It's not unlike the looks Bruce sometimes gives Tony when he's being particularly asshole-ish. Then, without warning, the pressure on her leg is lifted, and the beam clatters to the ground at her side.
Natasha stares at the beam, then at the Hulk. "Huh," she says. "Thanks."
He grunts, which she perceives as 'You're welcome'.
"Okay," she mutters. "Just like we rehearsed."
Well, not really. There isn't really a way to rehearse anything with the Hulk. But she's convinced Bruce to at least memorize the catchphrase, being careful to say it only when he's at his most relaxed. If they've played their cards right, then by now her words will be associated with things like safety and happiness.
Step one: get his attention.
"Hey, Hulk," she calls out. She's careful not to put an overly cheerful inflection in her voice. They have just spent the last few hours fighting mercenaries, and the Hulk knows a lie when he hears one.
His gaze fixates on her almost immediately. Good.
Step two: use the code phrase to reassure him.
"Sun's getting real low."
Well… at least he isn't trying to smash anything. That's… probably good. Although he mostly looks confused when he's looking at her. Which probably isn't good.
Natasha decides to improvise. Crouching down, and therefore implying that she isn't a threat, seems like a good idea.
Step three: initiate physical contact.
Slowly, she extends her hand. The Hulk looks at it, then looks back at her, clearly asking, "What do you want me to do with that?" Then he straightens up, huffs, and proceeds to rip a tree out of the ground.
Natasha stands, sighing. They can work up to it.
"Hey, Hulk!" she yells, just after he's transformed. "Bet I can smash more than you!"
He looks at her, and grins.
Four hours later, and Steve is staring at a dirt-coated Natasha and and equally grimy Hulk. He thinks she hasn't noticed, but Natasha notices everything. Even so, she's paying more attention to the green rage monster than she is to Steve.
"I got forty-two," she says. "You get more or less?"
The Hulk grins again, lets out what can only be described as a happy roar, and then bounds away.
"Uh… can someone please take out that sniper? He's being a pain in the ass."
"What, the sniper can't take out the sniper, Barton?"
"Save it, Stark." Boom. "Rogers, what was that?"
"Uh… mild explosion?"
"It didn't sound mild." Thud. Roar. "Oh. Thanks, big guy."
"Something up, Nat?"
"Nothing. Just got a, uh… present, is all." Alarmed yell, another thud. Another roar. "Glad to see you approve, Hulk."
"Hulk's happy that I punched the guy in the face."
"The Hulk brought you a guy?"
"Oooooookay. Ah, shit - seriously, can someone get that sniper?"
"Oh come on!" howls Stark. "You're not even trying!"
There's pain in his voice that says otherwise. The giant robot that they're fighting is proving to be a tougher adversary than any of them anticipated.
"I, uh, do need backup, here."
"Hang on, Stark," says Natasha's voice through the comm. "We're on our way, just give us about twenty seconds."
"What? I thought you and Barton crashed the Quinjet-"
"We were shot out of the sky!" Clint calls. "Oh my god, Nat, what're you…?"
At first Tony doesn't know what Hawkeye's babbling about, but it becomes clear pretty quickly: the Hulk is bounding towards him through the streets, and Natasha's… yeah, Natasha's perched on his shoulder.
The Hulk makes an even bigger leap, and Natasha uses the momentum to launch herself even further, bringing both of her batons into one of the 'eyes' of the robot. The thing pauses for a brief moment, which is more than enough time for the Hulk to smash straight into it.
"Romanoff!" Tony yells, because she's still on the damn thing. But while it's still falling, the Hulk climbs up it, grabs Natasha, and jumps to safety.
Later, when they're gathering their bearings after the battle is over, he looks at her and shakes his head. "I don't even wanna know, but I'm impressed."
"I overspent on ice cream," Natasha announces abruptly, barging into his place without knocking. She does this a lot - acts like she lives here or something.
Which, okay, she lives on the floor above him. So Bruce supposes she has her reasons.
Her arms are laden with shopping bags. Bruce watches in disbelief as she begins loading a wide assortment of flavors into his freezer, pausing every so often to contemplate the label and then (occasionally) leave the flavor on the counter.
"You like brownie fudge, right?" she asks him, not pausing to wait for an answer as she leaves the flavor out and pulls out a scooper. She gives him a heap of ice cream and passes it to him before grabbing a spoon for herself and opening the tub of mint chip, not even bothering with a bowl.
"So, uh…" he starts, not really sure what to say about this.
Natasha beams. "We're celebrating."
"We are?" At her look, he coughs. "Okay. We are. Why?"
"The Hulk calmed down when I told him to."
He raises both eyebrows. It's something that the two of them have been working on for months - albeit with some reluctance on his part. It had been Natasha who figured out that the addition of a physical 'handshake' was needed to really convince the Hulk, but he'd been reluctant to let her get close enough to try.
"Huh." He spoons some ice cream into his mouth. "That's good." I think.
Natasha jabs her spoon in his direction. "Eat your ice cream, Banner," she says. "Try not to sound so down about it."
He laughs. It feels a little more genuine this time.
They eat in silence for a while, Natasha not even pausing. He knows that she can work up an appetite that matches Steve's, but he's still surprised when it happens.
"You doing anything later?" he asks her.
"No plans," Natasha admits. "Why?"
"Well, we're celebrating, right? Might as well watch a movie, or something."
Natasha leans forward, smirking, and he can't quite stop his blush. She takes pity on him, and pretends not to notice.
"I like the way you think, Banner."