The easy pleasantness is contagious, anyone in her position Gus would expect to be sullen and withdrawn - not the sweet girl sitting across from him. It's pretty nice, really... and definitely a change from his mood when he walked through the door.

"You're telling me! Would you believe I've made friends with two goddesses, and a guy that reads minds?" He almost mentions The Devil, but there's no sense in admitting association with her at this point.