"I'm...I'm sorry," Derek said again, at a loss. No one should have to suffer like this. He knew that well, but...he couldn't even imagine something like that.
He shook himself as well, since Stiles seemed to want to drop the subject. "I don't mind, Stiles. I feel bad, even if it wasn't something I could help. And someone," he shot a look over to Erica's tank, "is going to get some lessons in manners."