They both left the place, without knowing that there had been someone else so close to them all the time. The moment the chief and the nerd entered the bedroom, Tianlong Yun got out of the window, and jumped on the roof.
He didn't need to be in the room to hear the words of the duo. He had his spirit sense, and could 'hear' everything perfectly from outside.
This was something he didn't expect, but now that he thought about it, it made a lot of sense. This was truly a good place to secure high class information.
And it was a good thing that he stayed and was waiting there, because a moment later he sensed that the chief of security returned to check the opened window.
But he was on the roof, and couldn't be noticed from the window, so it wasn't a problem to him. Just the chief of security seemed a bit disappointed.