The kiss from Gaius was quite chaste, but it still got a gasp out of the young girl. Sirius laughed. "Hm," he said thoughtfully. He didn't want to inspire too much curiosity about what sort of meeting a professor and someone from outside the school might be attending together. Denial, on the other hand, was often the most convincing argument. While he thought, he brushed his lips along her professor's cheek in a caress that was slow and sensual, but not technically more sexual than the one with which Gaius had greeted him.
"I think, given the audience, I should perhaps say a meeting," he said slyly. "A terribly important, solemn meeting, where we shall be lucky to get so much as a cup of tea." He flashed the prefect a grin and sketched a bow in her direction. "Thank you for your assistance, miss. Run along, now, so your professor can close up his office."
It wouldn't do for her to realize that they were staying in the castle.