MTL - Legend of Swordsman - Chapter 4 Bloody vow

The fat and ugly Nora Smith is the laughingstock of the town when her fiancé breaks off their engagement.

[ DING ][ Common Sense Hijack System Activated ]----That notification was the start of a whole new life for Karl. He who just used to be working at a convenience store and always getting annoying complaints from customers and some shady words from his manager. Become a totally free man who can flip common sense upside down!******

At 3 years of age, her father went missing. At 15, the muscle in her hand snapped. At 16, her mother passed away in a car accident. At 19, she was framed by her uncle. At 22, she was burned alive by her newly- wedded husband and her best friend. Perhaps it was God’s sympathy that allowed her to return to the time when she was 15 years old to re-live once more. The previous lifetime of being low- key and having forbearance resulted in betrayal and misery. In this lifetime, she must be lofty and domineering to let those who have bullied her suffer a terrible end!

- Description from Novelupdates

It was only after Su Yayan's death that she realized that she was a malicious cannon fodder female character who became a scapegoat in a Mary Sue story.