Nigoru Hitomi de Nani wo Negau - Chapter 73

Witnessing her boyfriend cheating on her with her bestie, Shiyao was so angry that she went to a pub for fun and met a man, who was really a piece of work. After a crazy night she fled away, but was embarrassed to know that the man she slept with was her boss You Ze.
Jesus, give her a break!

- Description from Novelupdates

The world was once at war with 10 alternate worlds. This was known as the Concept War and our world won 60 years ago. All of this was concealed so no normal people are aware of this fact in the current time.

After the death of his grandfather, the high-school student Sayama Mikoto is suddenly summoned by the giant corporation IAI. He learns this world is headed for destruction due to the acceleration of the Minus Concepts. To prevent this, negotiations must be undertaken with the survivors of the other parallel worlds so their 10 concepts can be released.

And so Sayama is caught up in the final battle to clean up after the Concept War which left behind so much enmity.

Mediocrity is the normal state of most people, and some of them can’t even reach the normal state~ A young man from a small town, ugly and inferior, disliked by relatives and friends, mediocre grades…

All these changes started with a beam of light going to the university train, and the boy was bound to the high-quality male god system.

The days are getting more and more hopeful, and the system is really fragrant:

As long as you learn, you can modify your own bugs;

As long as you do good deeds, you can get corresponding banknote rewards;

As long as you are praised, you can get relevant talent blessings;

…

This, it’s hard not to love, okay!

- Description from novelbuddy

She is an elder miss from a modern secret society family. She is very cold and heartless, but her appearance is very enchanting. She thinks of men as playthings. She was schemed against and her body was thrown into the sea.