Spotting the other woman, Chloe covered up her anger. Around Clark she didn't want to raise suspicion. Certainly if he knew the woman he may have already given her reason to be suspicious and snoop around. She's made a lot of bad decisions in her life but protecting Clark and his secret was always her first priority.
"I was about to ask you the same thing. Why am I here?! Where is here?!" Other things were going through her mind right now, like how on earth was this a part of his kryptonian destiny? But she'd have to ask him that later when they could be alone. Putting on a feign happy face Chloe turned towards Raven, pretending she hadn't noticed her. "I'm sorry, we haven't met yet." Reached out to shake her hand, "Chloe."