Long Jiu is not here

Why does it seem like I haven't detected the presence of Long Jiu?
In the darkness of night, under a roadside tree, a man dressed in black stood under the tree. His entire body was right in the shadow of the tree. He was like a ghost in the dark, completely blending into the night. Ordinary passers-by would not notice his presence at all if they did not look carefully.
Even if you observe carefully, you may not be able to discover his existence.
The man in black was staring at Ye Harbinger...