The supporting character's harem is very normal - Chapter 223 Meeting Rolen

By the time Li Qingran realized she had been transplanted into a book, she had already muddled through seventeen years.Growing up together as childhood sweethearts with the male protagonist Xie Ying’an, their relationship was rather passable.Endowed with the halo of the male lead, Xie Ying’an was like a hacked character from birth: good-looking, from a good family, with good academics...Li Qingran vaguely remembers that she was a female supporting character in the book, whose ending was not good due to constantly making trouble for the female protagonist.Li Qingran shuddered, feeling all too familiar with this plot; getting involved or not could both lead to trouble, so she needed to come up with some strategies to cope...PS: Unrequited love theme, male and female leads are high school students, and they do not engage in early romance.

Although born in a wealthy, powerful family, Shangguan Ning is motherless and loveless. Throughout her growing years, people use her for their own interests.

The hearse with the weird odor slowed to a stop before the entrance. The sound of pebbles could be heard bouncing on the ceiling. There were footsteps coming from the corridor, and there seemed to be someone sawing next door. The door knob to the room rattled slightly, and the faucet in the bathroom kept dripping even though it had been screwed shut. There was a rubber ball that rolled on its own underneath the bed. Wet footsteps started to surface one after another on the floor.
At 3 am, Chen Ge held a cleaver in his hand as he hid beside the room heater. The call he was trying to make was finally answered. “Landlord, is this what you meant by ‘the house can be a little crowded at night’‽”

- Description from Novelupdates

I returned to Earth as the invincible Knight King. But the Gods came with me.