No matter the reason why Wen Han hadn't called him, Su Mu still sent her a WeChat message, but he didn't tell her that he was staying at Bishui Yuntian. He felt that some things are better left unknown. What Su Mu didn't know was that Wen Han was always aware of his whereabouts because, due to work-related reasons, each vehicle of the Wen Family was equipped with a tracking device, and Wen Han only needed to check her phone to know exactly where the car was parked.
Before receiving Su Mu's WeChat message, Wen Han already knew that it was very likely Su Mu wouldn't leave that night. Yet, the message made Wen Han somewhat sleepless throughout the night.
Of course, Su Mu was unaware of this.