Becoming evil makes you ten times stronger, but becoming a demon gives you hundredfold strength - Chapter 437 - 345 Aunt Begs You for a Favor

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.

In the King’s game, the [King]’s order is absolute and has the power to create rules. As the owner of a special physique, Gu Huai was selected by the system to participate in the game. “Win the game and become the [King], and you can obtain whatever it is you desire.”

- Description from Novelupdates

After an accidental death, in order to continue to live, Gu Bai had to choose to go through various wonderful books to complete tasks.

Every time he became a variety of small cannon fodder inside the story, Gu Bai’s code of conduct when completing task is – by all means, don’t be inferior, don’t be shameless, don’t be upright… hold on to a golden thigh.

… N times after transmigrating

Cannon fodder: (angry contempt) … You’re already so powerful, why are you still shamelessly holding on to a golden thigh to deal with us!?

Gu Bai: (deadpan) That… holding and holding… got used to it…

Why is it “Hero” that “Savior” that? Why is it always the same happy ending? “Happy” “Good” “Perfect” endings? You know what? SCREW IT. I will give you all the worst possible ending possible? Why? Because I’m an asshole!