Derek just rolled his eyes. It was true that Stiles affected him unlike any other student could, and the headmaster often told him (privately and out of earshot of Stiles) not to let Stiles get to him so much. Derek couldn't explain why the kid go under his skin as much as he did, just that...Stiles was so annoying. Did any of the other teachers experience this much irritation around him? He didn't think so, they seemed to tolerate him just fine. Some even liked him!
He settled for ignoring him, in this particular instance, and finished feeding up the skrewts. "There, that's done," he said, climbing back over the fence rather than opening the gate - he didn't need anyone getting in or out, especially with Stiles hobbled. "Okay, onto the griffin - your favorite!" He grinned down at Batman, who trotted along beside him happily.