Here is the English translation of the provided text:
In the dead of night, Bian Yizhang stood on the rooftop.
The light in the east wing on the first floor turned on and off again. Bian Yizhang rubbed his eyes and sat up, knowing Jiang Yuan was about to come out.
He had observed this several times before and knew that the annex building of the Criminal Science Building of the 9th block in the Criminal Police Detachment was exclusively used by Jiang Yuan. Among them, the forensic doctor's most frequently used autopsy room was located on the first floor. Not only was it convenient, but the smell also dissipated easily.
Within the police system, this detail alone had already surpassed most forensic doctors' living conditions.
