Nicodemus hates Mouse

I stopped at the end of Michael's driveway and planted my staff on the ground. Nicodemus stared silently at me for a while. The shadows had shifted to mask his expression, and I couldn't see his face very well.
"What," he said in a low, deadly tone, "is that?"
Mouse stared at Nicodemus, and let out a growl so low that individual snowflakes jumped up off the ground all around him. My dog bared his teeth, showing long white fangs, and his snarl rose in volume.
Hell's bells. I'd never seen Mouse react like that, except in earnest combat.
And it looked like Nicodemus didn't like Mouse much, either.
"Answer my question, Dresden," Nicodemus growled. "What is that?"
"A precaution against getting stuck in deep snow," I said. "He's training to be a Saint Bernard."
"Excuse me?" Nicodemus said.
I mimed covering one of Mouse's ears with my hand and stage-whispered, "Don't tell him that they don't actually carry kegs of booze on their collars. Break his little heart."
Nicodemus didn't move, but his shadow shifted until it lay in a shapeless little pool between him and Mouse. His face came into view again, and he was smiling. "It's been a little while since anyone was quite that insolent to my face. May I ask you a question?"


Small Favor Chapter 37, Page 300-301