MTL - First Day In Game, I Got Ten Billion From Infinite Number Of Check-ins - Chapter 527 talk about

This is a story of a man named Kim Sae-Jin, who one day, inexplicably wakes up as a Monster. Follow him and his perilous journey to get his life back as a Human, all the while growing even more versatile as a Monster in the process. This should be… complicated, somewhat.

Since childhood Gu Wuji has regularly encountered ghosts and was one day involved in an infinite world of terror, just– I treated you as an evil spirit, why do you want to hug my thigh?

- Description from Novelupdates

Knowing she married a wrong guy, what would she do to deal with the subsequent marriage lives?

In order to pay for her brother’s medical expenses, she had to replace her own sister to marry the rich family's elder son . She always thought she was married to the elder one, but she did not know her husband was nominally the younger son He Yi Ning.

He Yi Ning, the real heir of the rich family, the ruthless business emperor, the ruthless workplace tyrant, and her sister’s dreaming husband. When she found out that the person who married her was He Yi Ning, she stunned and asked, “Shouldn’t i be your sister-in-law?” He smiled charmingly: “Are you unhappy with your husband?”