Evil MC's NTR Harem - Chapter 594 - Shackles

One day, Luo Jian woke up from his sleep and found himself in a locked chamber where the door and window were all sealed. A note with a few lines written on it was tacked to the wall: “Escape from this room within an hour, otherwise, you will die.”

There is a sequel called Reincarnation Night (轮回之夜) that takes place in the same universe but has different main characters

- Description from Novelupdates

It’s the age of superhumans!Genetic modifications, Cybernetic enhancements, magic enchantments- the choice is yours! For the right price, you can rise above the masses and gain power only ever seen in myths!For the right price!No matter how far humanity advances, power will always fall in the hands of the wealthy few. It was a truth Dante learned at a very young age and with it came a burning hatred for those who look down on everyone from their ivory towers.The flames grew stronger once he found himself faced with the cruelty of those who rule from above. He swore revenge on each and every one of them, but true power couldn’t be fought with hatred alone.In his search for a weapon that could help him take his revenge, Dante crosses paths with a certain Artifact, his fate taking a turn he could never have anticipated.

In order to live he must get close to girls, what kind of rule is this? Tang Zheng possess the Nine Yang Saint Body, a rare body constitution that is hard to come across within a millennium, yet he must absorb pure Yin energy to stay alive. In order to live, he will fight! Absolute campus belles, goddess teachers, charming housewives, haughty lolis… all kinds of woman walk into his life causing him to be surrounded by beauties!

A mecha otaku is reincarnated into another world as Ernesti Echevalier (Eru). In this world there exist huge humanoid weapons known as Silhouette Knight. Dreaming of piloting those robots, Eru, with childhood friends, Archid Walter and Adeltrud Walter: together they will aim to become a Knight Runner, pilot of Silhoutte Knight.