Zhou Xi's mouth could be described with a Chinese idiom, Seven Mouths And Eight Tongues. It was used to describe a person who was gossipy and meddlesome.
It had just been mentioned that he was once severely beaten abroad, thus he would sometimes feel an ache in his neck due to an old injury. Therefore, he needed to move his neck from time to time to relax it after he maintained a position for too long.
After he finished eating, he slightly moved his neck and made a sound of "Ka Ka". Actually, the exercise wasn't the main point.
What was important was…
"What's this?!!" Zhou Xi stared at the ceiling fixedly in astonishment.
"Is the painting above the authentic work of People Passing by A Small Restaurant?"
As he was much too surprised, Zhou Xi failed to control his voice. As a result, everybody heard that and looked towards the ceiling after him.
