Like a comeback, except with flirting. Used when one, most likely a romantic interest, flirts with another who returns with another comment. They go back and forth to attempt to playfully out-flirt the other.
Cody: "Did you just hear Thomas out-flirt Stanford?"
Jules: "Yeah! He couldn't come up with a flirtback afterwards!"
Jules: "Yeah! He couldn't come up with a flirtback afterwards!"
by GOLDFISH. February 11, 2018