Can track scents

Billy scowled at me, but he left the pizza alone. "So what do I do?"
"Sit tight and make sure no one else tries to pop me while I'm talking to Toot-toot."
"Toot-toot?" Billy asked, lifting an eyebrow.
"Hell's bells, Billy, I didn't pick the name. Just be quiet. If he thinks there are mortals around he'll get nervous and leave before I can snare him."
"If you say so," Billy said. "I was just hoping to do more good than to deliver pizza."
I raked my fingers through my hair. "I don't know what you could do yet."
"I could track those three in the picture you showed me."
I shook my head. "Odds are they just got into a car and left."
"Yeah," he said, some forced patience in his voice. "But if I get their scent now, it might help me find them later on."
"Oh," I said, feeling a bit stupid. Okay, so I hadn't considered the whole shapeshifting angle. "Fine, if you want to. Just be careful, all right? I don't know what all might be prowling around."
"Okay, Mom," Billy said. He set the pizza box on top of a closed trash can, fell back down the alley, and vanished.
I waited until Billy had gone to find a nice patch of shadows to step into. Then I closed my eyes for a moment, drawing up my concentration, and began to whisper the faerie's Name.

Summer Knight Chapter 13, Page 153-154


"Gotcha," Billy said. He glanced back at me. "How'd it go? You get what you needed?"
"Yeah," I said. "You?"
He shrugged. "Alley isn't the best place to pick up scents, but I should be able to recognize them again if I'm in my other suit. They didn't smell quite normal."
"Gee, what are the odds."
Billy's teeth showed in the dark. "Heh. So what are we waiting for?"

Summer Knight Chapter 13, Page 162