The Scum Is Repressed
Cheng Sheng has already visited Jing Rui along with the others before, so he doesn't need to show his face again, since Zheng Yi's life and Lei Ling's life are on the line. Jing Rui may be gravely injured, but not to the point it is life-threatening. It's just that, the longer his injuries were left totally cured, the bigger his chance to become invalid.
It happened during one of their rescues. They were going back along with the people they saved when Jing Cheng found an orphan on the street who was crying loudly. Jing Cheng wanted to save him, but the demonic cultivators were hot on their trail. But, Jing Cheng just can't leave her alone. She reminded him of himself before Jing Bai's and Jing Hei's parents took him in.