MTL - The Head of My Family is Number One In the World - Chapter 7 Broken arm and broken leg

Evolution, it is the process with which the most fit for survival pass down their winning traits. What if this could be done on one animal, one object, one person, what traits would evolve.

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Humanity has been entered into the grand inter-realm competition for sovereignty of all realms.

Darwin has been granted the gift of evolution

Haruto Hayase was a normal high school boy in his third year, living a quiet life until his younger sister, Haruka Hayase, joined the same school. Haruka’s beauty and charm made her the center of attention, quickly becoming the school’s prima donna. But when a notorious gang leader set his sights on her, he did everything in his power to protect her—only to fail tragically. Haruka was brutally assaulted and tortured, and Haruto himself suffered an agonizing death. However, in a twist of fate, Haruto is given a second chance, waking up a year before the events that shattered his life. Armed with the mysterious ‘Debauchery System Slave’, he vows to exact revenge on those responsible. This time, he will use his newfound powers of the system and charm to seduce the loved ones of his enemies. From their mothers, sisters, and lovers to their closest friends, Haruto will make them his. His enemies will suffer as he steals what they hold dearest, ensuring their downfall in the most devastating way possible.

Qin Xiaobai transmigrated into a husky.
And his master turned out to be a goddess-level live broadcast.
Reporter: “Miss Su, you are now the first sister of Douyu. What’s the secret of your success, is it your good looks or hard work?”
Su Wanqing thought for a long time, then pointed to Erha beside her and replied, “It doesn’t seem to be the case. The main credit for my current achievements is that my Erha is so outstanding! Sometimes I even doubt that my Erha is the protagonist. …”

- Description from novelbuddy

Revenge is a dish best served cold, with dollop of whipped suffering and a sauce of acute humiliation.Karma would do anything to exact revenge on the one who was responsible for her mother's death, her father's disdain and distrust, and a miserable life.She was manipulated, maltreated, and humiliated by the one she trusted the most. Her stepsister!!Discovering she had only three days left to live, Karma would go to any length to exact revenge. Even offering herself to the scary and powerful demon overlord.A contract. Blood oath. Manipulation. Betrayal. And lots and lots of revenge.