C110 Brush Integral

As he laid on his bed, Zhang Yunfeng made two rough plans in his mind. One plan was to find a way to stealthily sneak into the Hilton Hotel and kill the killer in his room; the second plan was to stay in front of the Hilton's door and wait for him to come out before following him. Zhang Yunfeng would choose a suitable opportunity to make his move outside of the inn.

At first