Tony hacked into Natasha's phone and when he went through her photos, because he's snoopy, and found a bunch of pictures of Clint so he decided to embarrass her about that night during the movie.

"hey Nat" Tony says "yeah" she replies still looking at the tv "so please don't kill me but" he starts "what did you do" Natasha glares at him "ihackedintoyour phone" he rushes out "you're lucky I don't have any weapons near me" Natasha says lowly "uh huh so anyways as I was looking through your photos I found something interesting" he tells everyone "did you delete my blackmail" she asks "no" he answers "good" Natasha nods "so back to what I was saying I found something interesting which was that you have a whole album of pictures of Clint" Tony smirks "they're blackmail?" Natasha says "no cause they're good pictures" Tony shakes his head "I would hope I mean I am her husband" Clint says "her what" Tony asks shocked "nothing" he replies.

Clint runs into the vents with Natasha following him and they weren't seen for a few days after that and when they were Clint had a lot of bruises and Natasha's face held a smile.
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I have no idea where I was going with this