Chloe had no one to talk to in this class, she realized as she looked around, then she walked up to the empty chair and sat down. As she did, she looked around one more time to see someone she didn't see before. 

Zach was sitting in the corner with Liam, and they were facing the back of the class with their back to her before when she walked in. That must be why she had missed them. 

Quickly before he saw her, she turned back to face her front, telling herself not to look in that direction ...