"Feh," he snorted, turning his eyes away from the other man and setting them back on the door. He didn't like being told things like that. It was too much like when the kid had called him kind. "Don't say stupid things," he ordered as though Zabuza would listen. He didn't care if the guy related or whatever; he was only doing this because Fai wouldn't get it otherwise.

That's perhaps why the comment got under his skin so much.