Draco had felt like responding with 'Sorry, I must've left it in my other suit' to Gilderoy's question but it was perhaps a little too much snark. To the best of his knowledge the man wasn't even intentionally being annoying. Unfortunately, his personality, mannerisms and Draco's disbelief in his accomplishments generally just seemed to irritate him without any effort at all.
From the back he thought the lady seemed familiar and even managed to stop himself from laughing when Gilderoy introduced him to none other than Lottie herself. He brought up her hand to kiss it before mouthing 'thank you' to her.
"Well, I do like my privacy," he replied. "I'm sure if it had been any other young lady they would've gotten over it soon enough."