Lu Zexi didn't know where Shen Huizhu came from or what his purpose was.
But Shen Huizhu said: "I love you"
That's enough.
The rest will be said by Shen Huizhu himself when the time is right.
Lu Zexi: "Where's my dog?"
Shen Huizhu: "I was let go by Ruan Yi."
One minute later
Shen Huizhu: "I picked it up, my dear."
Lu Zexi: "Oh."
Purpose: To heroes