MTL - Imperfections - Chapter 14 It's our turn to capture the waves

On a certain day, Xu Xing suddenly received yin-yuan eyes; he could see a red string between lovers. Then he discovered that he had a tight connection to his own left hand.

Xu Xing: I TM …… will I be ‘solo’ for life? : )

The second day.

Xu Xing suspected that he had seen a pair of ‘gay’s. The left side of the boy’s body had two red strings. The one in front was tied to his hand, the one in the back was tied to the boy’s right side.

The bottom of Xu Xing’s body suddenly tightened. Trembling in fear, he turned his head — only to see his ‘local area’ connected to a red string tied into a beautiful, intimate bow that was attached to the school grass sitting behind him ~

Xu Xing: Excuse me???

- Description from Novelupdates

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.

The Supernatural era descended, the rules changed, mystery arrived, and the world altered. Countless ruins of civilization emerged, and an abundance of Heavenly Materials and Earthly Treasures lay at everyone’s fingertips. Radical faction, “This is the best of times, entering a new world, excavating relics, mass evolution!” Conservative, “This is the worst of times, with countless monsters outside, once you leave the Safe Zone, extinction awaits humanity!” … Meanwhile, at a remote ruin, Lu Yuan successfully discovered new treasures and sought after the mysterious wealth, desperately trying to contact his fellow Earthlings. “Found a communicator, can it get through?” “Hey, humans—I’m almost becoming a god, and you’re still hiding in the Safe Zone?”

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