Holding Onto My Man - CHAPTER 18: FANTASY CINNABAR MOLE

Roy’s life was nothing special. The only thing commendable was the last few moments when he saved a mother and her child from a drunk driver.
…
It’s really an egg! Damn it, what kind of monster have I become? Did I fall into Hell instead of making it to Heaven??
Join Roy as he ventures through various worlds with the Custom Made Demon King System—a system that allows Roy to draw anything he can imagine and create it through exchanging souls!

It was supposed to be a perfect deal in which both parties got what they needed. However, after the child was born, he tore up the agreement with discontent and told her, “Who said that we’d only have one child? I want twins! Twin brother and sister! You’ll continue giving birth to more children until you bore me a pair of twins!”

While she was opening and closing her eyes, Mu Rou Sang had finished her transmigration.

“Her background was miserable, her family was ruined, she had no parents, and she had no brothers or sisters.”

She only had one brother who was dependent on each other.

- Description from Novelupdates