Dungeon Predator - Chapter 12. Sewer’s Secret

In the tenth year after the new era, the world finally came to an end. Zhang Mu truefully waited for his death, but unexpectedly found that he had returned to ten years ago. With his memory about the future, he swore that he would change the calamitous history, saving the earth from being destroyed! Walking dead, zergs, evolvers, and various mutated animals… nothing can stop him! The first step is to retrieve his identity as an era merchant , then find all the treasures he can remember to enhance himself!

- Description from Novelupdates

She, Xue Fanxin, a famous medical genius in the 21st century, had transmigrated into the body of the dumb daughter of the Grand Duke.

In a galaxy far away, there is a kid without innate ability to practice internal techniques. So, in order to gain the respect of his father, he resolutely chooses to follow the more difficult and painful path of practicing external techniques. As the years go by, he grows up, but what really changes his life is a mysterious meteoric crystal stone – the Meteoric Tear. This stone fuses with the young man’s body unnoticed, and he seems to undergo drastic transformations as a result. After that, everything is changed. Eventually his father knows that the son for whom he hasn’t really shown a lot of consideration possesses astonishing abilities. And there’s a lot more to come.

Being able to see into people's past has no real appeal for the teenager this story is about, letting him use it only as amusement and to show off when he was drunk.Never watch into someone's past beyond a superficial level.Never try to find out more than you should.NEVER. EVER. LOOK. INTO. THE. FUTURE.But everything changed the moment he was forced to look into the future, was forced to investigate a murder, and was forced to make the acquaintance of the victim's twin brother('s fists).The more time passed, the more it appeared that the primary reason for this murder wasn't a local problem, but a global one.This single, marred corpse was the beginning of a threat that would shake the world.(MC looses a screw when he enters the prison)BL, first-person view; MC is shuo (perhaps even a reversible couple); love interest falls in love first; both MC and ML are straight, mutual bending, Enemies to Lovers