A/N: Prompt: "Wait, are you jealous?"

Bruce takes one look at the time, yelps, and starts stuffing things into his bag.

Tony is in the middle of rambling about advanced hydraulics, and thus doesn't notice Bruce packing up until he's got everything and is now struggling to shove his glasses in his pocket. Tony's speech slows to a stop; Bruce meets his eyes and pauses, fidgeting awkwardly.

Tony is the first to speak.

"Okay, normally you're not one of the people who runs away when I start talking science."

"Sorry," Bruce says. "Sorry, just, I have to go - "

"Eating is for the weak."

Bruce sighs. "Tony…"

"Look, if you're really that hungry we can order pizza - "

"I'm already late, and Natasha's - "

"Whoa, whoa. Hit pause, buddy." Tony stares at him like he's insane. "You're canceling science time to have dinner with Natasha."

Bruce feels his ears burn; Tony says it in a way that Bruce has been purposely avoiding since Natasha first proposed the idea. "I think she said something about making sure that I actually have vitamin D in my system?"

"Oh, so it's that kind of dinner."

Bruce gives him his best deadpan look. Tony, meanwhile, is pouting like a child.

"Are you jealous?"

"Yes," Tony says. "Yes, I am very jealous, and you should definitely indulge my jealousy before it consumes my soul."

"Sorry, Stark. You don't get a monopoly on spending time with Bruce."

Bruce whirls; sure enough, Natasha is leaning against the doorframe, smirking at the two of them. She's dressed casually, which is a relief because Bruce definitely does not have time to change. He looks back at Tony in time to see him make a face at Natasha.

"Be nice," he admonishes.

"She just made a face back at me!"

Bruce looks back at Natasha with one raised eyebrow. Natasha shrugs, apparently unapologetic. "It's true, I did."

Bruce rolls his eyes, but moves over to Natasha, waving at Tony as they leave (Tony's gone back to pouting). Natasha puts her hands in her pockets and nudges Bruce with her elbow.

"Hope Stark isn't too heartbroken."

"He'll be fine," Bruce replies. A grin tugs at his mouth. "That's his way of saying he's happy for me."