[Sanji has no reason to do anything but smile, though it's slow-moving and a little unsure. She just... told the truth, and he isn't sure how to read that.

There's a pause on his own end before he decides to just move forward and play the fool.]

Aaah, I thought that was you~! I had no idea you knew how to play the guitar, either. [Or knew Bink's Sake for that matter, but he guesses that's what happens when a pirate skeleton musician is one of your best friends]

Brook would be pretty damn impressed.