A Hundred Times: Ascending With The Strongest System - Chapter 1: Prologue: Breaking Free

Protagonist travels between different anime worlds to right wrongs and uncover his reason for being along the way.

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

There was nothing left to lose in his life.He had lived as a hero. He had started at the bottom and worked his way up to the top, at the end he become the best, yet he had always been betrayed by those he had tried to protect.Humanity did not deserve his protection.When everything went out and he could no longer even hope to beg for his life, he could do nothing but look up at the blood-red sky among the corpses of demons and angels.He wished for one more chance, just one more chance.And when that chance was given to him, he swore that he would change everything. He would no longer be a hero to save people, but an anti-hero to save the world.Sacrificing hundreds of people to save an elf, poisoning hundreds of people to save a group of half-demons.He didn't care about any of that anymore, he would protect those he cared about and send everything else to hell.Not even the gods or goddesses could stop him.

A minus’ hand that fails every singer he put his hands on, Kang Yoon.