What's so funny about this?

.She felt that after Fu Mo Han turned off the light and lay down, there was no movement at all, as if he had fallen asleep.It's kind of unexpected, he fell asleep so quicklyFu Mochen was indeed asleep...his small hand shaking, and his grandmother's voice held a firm tone, "Your expression gives it away."Su Han was unconvinced, muttering, "What can an expression tell you""You're not happy that I said...