Avoid Yandere Constellation - Chapter 150:

Growing up parentless, Shi Yan, who was left with a large inheritance money, bore a general disinterest in life.

The only times he felt alive was when adrenaline coursed thorough his veins. He quickly found that extreme sports, bungyjumping, cave diving & skydiving, gave him the biggest kicks. The bigger the adrenaline kick, the closer he was to death, the more alive he felt.

Waking up in a pile of dead bodies in an unknown land, after a diving adventure had ended disastrously, he quickly realizes the body he now possessed was not his own.

Follow Shi Yan as he explores this new world where danger lurks around every corner, and death is only a breath away; a world in which Shi Yan could not feel any more alive.

- Description from novelupdates

He was aloof, reticent, and indifferent to women. Many girls expressed their liking for him, but he refused all with three sentences: “No way,” “No need,” “No possibility.”Except for one person—her.Since she moved in and lived with his family, he changed a lot. The used-to-be aloof guy not only helped her with her homework but also protected her all the time. He liked to tease her every day.“Be good. I'll let you kiss me.”“I will only answer your questions.”“One wrong letter, one kiss.”

Waking up in the body of a 6-year-old boy a few years before Cintra is destroyed, Madara receives a system that gives him the ability to gain the powers of Uchiha Madara.[The peak of Uchiha Madara's system is before he becomes the ten-tails jinchuuriki.]The system's percentage does not stop Madara's power, but rather the system's release. After all, I don't want to see a character who goes around killing everyone from the beginning of the story.