(Um, Sorry) I’ve Been Reincarnated! - 020 – First Lesson

In a world consumed by monsters and chaos, survival is a cruel game of fate.Every year, the system selects a group of unwilling teenagers by lottery to fight, a death sentence Olivia didn’t ask for. Betrayed by her family and forced to fight, Olivia barely escaped death.In her near-death encounter, her system awakens….. only to deem her abilities “Useless”. But a chance encounter with a mysterious white snake sets her on an unforeseen path.Now, with the monsters lurking in the shadow, she has one goal: survive, grow stronger, and uncover the truth behind her fate.Survival is just the beginning. The real war is yet to come.

Xu Mo, a modern high school student was sent back in time to Jing Kingdom and found herself trapped inside of the body of a princess with the same name.

She had barely recovered when she learned of an unparalleled fiancé and in a daze, they got married. Then the stunning genius physician who normally does not pay attention clamoured to marry her. After that, there was a cold general, a flirtatious lord, a tsundere young master……

As it turns out, this was a male-dominated dynasty. Because the female population was sparse, the entire nation shared wives regardless of rank or nobility. Is it feasible for someone who wants to maintain monogamy in this dynasty?

- Description from Novelupdates