Carol / Clint
"People never plan on it in the beginning." Carol pointed out, nodding to the eye. "Bet you didn't plan on that today, either. But it happened. So I'll say it again. You hurt her, I'll hurt you."
Sure, Clint had known Nat far longer than Carol, but Carol was...protective. Extremely protective. And Natasha was the first truly close friend she'd had in a very long time if she hadn't mentioned that. Could anyone really fault her for wanting to make sure the woman was safe?
"She loves you. You know that. She's been through enough and she deserves to be happy. We're just going to make sure she stays happy."