Living with the Dangerous Beast - Chapter 8: Karma

Kaito Nakamura, a shy university nerd, thought he’d found love when the stunning Aiko chose him as her boyfriend. Their sweet, fluffy romance fills his lonely world with hope—until he discovers she’s cheating on him with multiple guys, reveling in the taboo thrill of betraying someone so innocent. Heartbroken and humiliated as explicit photos of her circulate online, Kaito’s tears are interrupted by a mysterious popup: the “Revenge NTR System Beta.” Promising retribution but with a chilling condition — he can’t break up with her.Contains Ntr, read at your own risk

An editor at the prime of her life—and with maybe just a little too much free time—finds herself waking up in one of her favorite RPGs with no clue as to what's going on or how to get back home.This might be the part where others rejoice over getting whisked away to a world of wizards and magic, but she certainly doesn't think it's anything to celebrate about.After all, she woke up in the body of a small-time villain with some severe personality issues.

When Yuan Zhi met Song Jiyun for the first time, Song Jiyun was conspiring with her brother-in-law to take over the family business;

When Yuan Zhi met Song Jiyun for the second time, Song Jiyun was planting and framing others with her breast brother;

When Yuanzhi met Song Jiyun for the third time, Song Jiyun’s breast brother was no longer by her side, but she was winking at his good brother…

Scholars can bear it, but he can’t bear it. Yuan Zhi decided… to feed the tiger with his body, and took Song Jiyun, a demon girl!

- Description from novelbuddy

This world has Fox Fairies, River Gods, Water Monsters, Great Demons and Cultivators who seek immortality.