Doomsday Lord - Chapter 277:

Tianshu Fengshen list, Di Shu Shan Hai Jing, human book life and death book!
Above nine days, it is for the fairy palace!

- Description from ptwxz (translated)

[Your shadow is alive.][Feed your shadow, devour souls, level up, gain skills, complete quests, and grow stronger.][Do you wish to view your current stats?]In the magical world of Aetherus, Damon Grey is the weakest student at Aether Academy, relentlessly bullied and ridiculed for his lack of power and defiant personality. Yet, he endures the torment, clinging to his scholarship—the only thing providing him with the funds to keep his sick sister alive.After a brutal attack leaves him near death, Damon encounters a dark viscous entity in the forest that fuses with his shadow, awakening the Living Shadow System. This strange power grants him unimaginable abilities but comes with a grim cost—a relentless hunger for souls and flesh to feed his shadow.Now, with his shadow alive and insatiable, Damon faces a terrible choice: feed it to grow stronger or starve it and die with it.In a world ruled by ruthless nobles, deadly monsters, and power-hungry demons, Damon must decide if his newfound power is a curse or the only way to survive. With the Living Shadow System, his fate is clear: devour or be devoured.

This is the 40,000th year that the Empire has ruled the Milky Way. The glory of the Great Crusade has long been lost in the dust of history. Su Yu traveled through time and opened his eyes to see the ruined planet in front of him, with a confused look on his face.

On this planet, there are extremely dilapidated war machines that stretch for thousands of kilometers, alien behemoths whose roars can shatter mountains and rivers, and radiation that can cause further damage to the surrounding environment just by moving. Alien beast——

There is everything here except hope.

Regardless of whether he wanted to or not, Su Yu, who had struggled to survive for three years and was inevitably infected with radiation sickness in the end, seemed to be one of the desperate people.

Until his career panel, which allows for unlimited career changes, was finally opened.

“Ding!”

“It is detected that the host has met the prerequisites. Do you want to take up the occupation [Mechanic]?”

“After completing this profession, you can gain professional experience and improve your professional level from daily maintenance, recycling, and assembly of mechanical creations. With each upgrade, you can gain an increase in physical fitness…”

Looking at the old gun parts piled up in his repair room, Su Yu’s eyes lit up like never before!

Many years later, at the core of the empire, at the highest point of the Terran world, the mechanic from the Ruined Star, the Ghost Shadow Blade of the Dead Wasteland, the restarter of the Titan Weapon Plan, the Governor of the Broken Star Territory, the Lord of Mechanical Ascension, the Supreme Throne of the Forge World, Su Yu looked at the torrent of steel coming from below and waved his hand to give the order!

[Our goal is to make the (second) (crossed out) empire great again! 】

- Description from novelbuddy

Set on a giant, almost finished bridge between Sadogashima and Niigata. Abandoned by the government, the bridge, and the giant man-made floating island at the center, has become a city of criminals and societal drop-outs.

Set in the same world as Durarara, but 15-20 years later. There is almost no overlap between Etsusa Bridge and the other novels.