At a better time and place, Nikolas likely would have been willing to at least hear Daphne out and keep any negative thoughts to himself. While he wasn't quite at the point of disclosing any and every unkind thought that crossed his mind, he was also quickly becoming cranky and somewhat indifferent. As a way of compromising, then, he let out a quick, derisive snort, but almost immediately followed it up with his latest attempt at helpful words.
"Sorry." Throughout their infrequent and short-lived interactions since the beginning of term, Nikolas had found that whenever Daphne got on this topic he became very uncomfortable - he didn't really know what the right way to respond to her predicament was, or if a reaction that would ordinarily go over well with someone else would work with her. He was much more used to, and ready to respond to, people who were straight-forward and didn't carry tons of baggage behind a facade of vanity.
At the core of it, Nikolas felt like he shouldn't be the person Daphne was opening up to like this, even if - especially if - it was because her judgment was probably impaired at the time. To him, it wasn't his place. Or maybe he just didn't want the responsibility, or to feel like it was his. So, though he was still facing her, he made a point of avoiding direct eye contact, which made for an odd effect.
Still, he felt he needed to say something or she'd just keep on going. "What of, then?"