Percy could only stand and gawk for a moment, staring at the back of the other man's head, not quite able to believe what he'd just heard. If nothing else, he finally managed to think, it certainly proved Mr. Tepelus had just been being rude when he'd referred to Minister Grindelwald by his first name - there was no way the Minister would surround himself with people who used such crude language. 'Piss him off,' indeed.
Regaining his composure, he followed the vampire, catching him up, and twisted his hands into fists to keep them from reaching for his wand. "Certainly," he said coolly. "From a first-person perspective, I've no doubt."