Over-laid comment in the mainland of China is usually defined as the comment that inserted on top of the video feeds. It is time-synched and flows over the frame from right to left. This essay attempts to analyze the operation of over-laid comment system in a critical perspective, compare over-laid comment pool to Le Drugstore, and argues that the comment is first perceived as advertisement from viewers, which stimulates them to use that function. Sending over-laid comment, which is heavily routinized, is like writing poetry or solving riddles in a virtual panopticon, thus the relationship between media and audience in over-laid comment system hasn't been altered. The essay indicates that the pleasure and freedom obtained from newly formed over-laid comment system will cost more than they do in traditional media.