The meaning is simple and straightforward: the one who opens the door must be responsible for closing it, those are the people abandoned by the world.
However, in this world, there are always people willing to be the last to close the door, holding the line for everyone.
Lu Yuan looked at the sorrowful expressions of his subordinates and said with a smile, "Don't worry, the boss has made a plan for me, I won't die."
...
...
The reinforcements from Deer Island arrived, looking at the empty main entrance of the music hall, they sought out a witness and asked, "Where are they?! Which direction did they go?"
"They all went inside!" the witness informant responded, "I saw it with my own eyes, their thousands of troops all entered the music hall."
The heart of the Garrison Commander sank, it's over!
This place has been taken hostage!