I like specifically how Sazh and Hope sum up how normal people would react if they ever were interacting with the other characters. The perfect examples for me are when Lightning talks about chapter 3 spoilertaking the fight to Sanctum's door and Sazh initially thinks she's joking, then after a pause he turns, surprised, and says "You're serious!?". The best example is still Hope's reaction to Vanille when she wants to explore the Vestige though. His twisted expression made me laugh loud.