[Elsa visibly jumps as Lup's voice, and a light crack can be heard as her claws dig into the wood of the broom in her hands.]

Oh, Lup! [I was really hoping you'd change your mind!] I didn't think you'd get here so soon! Um-- if you want to take a break, would you like something to eat, or...?

[Even as she's talking, Elsa doesn't stop moving, instead heading behind the counter to put her broom away, and possibly grab something from the case if Lup wants it...!]