There are many ways a self-respecting (not to mention sane) teenage girl might react to having a teenage boy suddenly in her bedroom in the middle of the night.
Hit.
Panic.
Flail.
Freeze.

My name is Cammie!” I didn’t think about all the people I could have woken, all the alarms that might have gone off. I just snapped, “How did you know about Boston? Why are you working with Mr. Solomon now? Are you my friend or are you my enemy, Zach? Or, wait, let me guess, you can’t tell me.

Spy.

I wanted to pull away, remind him that I was a big girl, a highly trained operative, a spy - that I'd been training for this mission my entire life, and I wasn't going to be left on the sidelines. But in the dim space with Zach pressed tightly against me, only one thought came to mind. I kissed him - longer and deeper than I ever had before. The school was not watching us this time. There was nothing playful in the tone. We were just two people kissing as if for the first time, as if it might be the last.

And then I broke away. "So," I asked, as if I got kissed like that all the time (which, believe me, I don't), "where is it you're taking me again?"

"The tombs.

She thought she was only seeing him because she wanted to see him... It's a by-product of very dramatic kissing.

I never knew there were this many stars."

"I can't see them," he told me. "I just see you."

"That's one of your cheesier lines," I told him.

"It's the altitude," he told me. "I don't have enough oxygen in my brain."

"I see.