Republic Reborn: Against the Stars and Stripes - Chapter 2: Betrayal

He kept her by his side, never letting go! “Please, can you let me go?” “Impossible,” he said, “unless you're no longer my only one.” After they fell in love, he declared possessively, “I want to keep you by my side, to make you belong only to me. You can only love me too, your mind, your world, must be filled with only me.” Yet his domineering love sent a chill through her.

Lou Yao Yao wasted her life fighting over a man, only to find out he wasn’t worth it in the end. Because of this man, she accidentally killed her rival in love, and even ruined the man who had always been watching over her.

Getting reborn as her 20 year old self, there is still time to fix everything. Lou Yao Yao decided to live as a genuine vicious woman. After getting her hands on the loyal like-a-dog man, she would show that cheating couple what pure loving affection looked like.

- Description from Novelupdates

The protagonist, having degenerated into a “loser” after being unable to find employment, gets caught up in someone else’s attempt to commit suicide-by-train and ends up traveling to another world. The numerous cheat powers he demands from God are all granted to him. But contrary to expectations, these powers bring about disastrous consequences for the protagonist.

Having reincarnated into another world, the optimistic protagonist (Yuuri) starts his(her) heart-warming training days with his(her) teacher.

One day, Su Mu transmigrated to an alternate world.This world had martial arts practitioners, Qi cultivators and also various types of terrifying ghosts, monsters and demons.In such a hostile environment, his otherwise-perfectly fine reincarnation system became a death system. For him, death was not the end, but rather, a new beginning. From the system, he experienced the profane lives of tens of thousands of demons! In one simulation, he was cut up, thrown into a pot, and eaten. Then, he became a Bloody Skeleton. In another simulation, he was forcefully conscripted and died in battle. His corpse did not decay, and he became a Drought Zombie. In yet another simulation, he was struck by lightning, and his extreme Yin Qi was converted into Yang Qi. He became a Fierce Thunder Ghost. In one more simulation, he consumed spirits, and his murderous aura filled the skies. He became an Undying Ghost Chariot. Some people cultivated to become deities. One other person died a hundred times to become a demon!