After rebirth, I rejected the rich yandere lady - Chapter 17 - Are Girls These Days All So Proactive?

Kaiden Tian’s aspirations of basketball stardom take a heartbreaking turn when a car accident not only claims his mother’s life but also robs him of his ability to walk. Undiscouraged, he settles for a role as the waterboy of a top high school basketball team, determined to stay close to the game he loves. However, he meets an untimely death and finds himself inhabiting the body of Kai Guo, a notorious troublemaker blessed with an ideal physical form. [Welcome to the Rise to Legend System!] With this second chance at life, Kaiden sees an opportunity to rewrite his destiny and fulfill the dreams that were once shattered.

She, a modern hidden ghost leader of an organization which gathered insane prodigies proficient in the various differing skill-sets. Highly skilled in medicine and poison, executes covert assassinations, viewed as insane and demonic in the eyes of people of the world. Killed in an accident, and reborn into the body of a disfigured young girl.

What? Face disfigured, identity stolen? A return to the family dim and hopeless? Her identity can be given up, her family can be forgone, but as for the one who harmed her predecessor who inhabited this same body, if she didn’t at least make them scream in unimaginable agony and throw them into a state of wretchedness, how could she live up to her demonic reputation? Endless turmoil ensues and it’s a battle to dominate over all! See how she shook the world dressed in a suit of red, her sword up against the dominant powers that rocked the Heavens! Her name spread across the seas, shocking the earth!

- Description from Novelupdates

As a promise, he went out into the world as an assassin. 3 years later, after becoming the Supreme Assassin, he gave up on everything he had and returned to the ranks of ordinary people. But one day, Kismet, a mystical game created by the National Research and Development had appeared.

Enigmatic hands, spectral frame, and one cunning strike just like the swing of the Grim Reaper. The Supreme Assassin takes on the mystical world, and how his legendary tales sets off, progressively ascending the altar to becoming the best.

- Description from Novelupdates