They've got something like an equal exchange of getting under each other's skin. She's been doing it to him since they met.
"Instinct," which doesn't mean he understands, but he's trying to be supportive. A better version of supportive than he was when she saw Anakin's ghost, and he is steering her further away from the dance floor and toward food. "Would've kept you from getting dropped, if I'd been worse at that than I was."
That last part is admitted with a grimace he is only capable of when admitting he's wrong.