He doesn't bow back, if that's what he's supposed to do, but he does give her as polite a smile as he can. He wished he could tell her something different or give her a reassurance she's asking for, but he couldn't. They simply didn't know enough about where they were to make those kinds of promises.

"If I said yes, would it make you feel better? I was taken about a second before I prevented an evil force from destroying my planet, so I understand wanting to get back to something important. Unfortunately, we just don't know. I saw one girl who had been on the train leave through the ticket barriers but I don't know what was waiting for her on the other side." He sighed, glancing at where what's-her-name vanished. "Look, you're welcome to hold on to whatever secrets you have for now. Just keep in mind we're your allies here and want to keep you safe. If you need anything.. you're welcome to come find me."