[He doesn't, but there happens to be one just offstage. He grabs it, caught up in the spirit of things.]

I'm a little rusty. Guitar was never my strongest suit.

[...he warns, but as he starts playing he's perfectly competent. More than competent, in fact - he's pretty darn good, and the audience is reacting quite positively as his fretwork complements Garnet's keytar jamming.]

[Funny how that's working out, huh?]