A Summoner? - Chapter 216: Concluding My First Campaign?

A teenager named Evan Mason was reincarnated into the magical world of Harry Potter and goes to school at Hogwarts!
With only his knowledge of the future and great talent for magic, he takes the path towards the top of the magic world, only to realize that ever step he took, changed everything!

- Description from Novelupdates

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.

A magical 'Universal Toolbox' led Joe Ga into the arms industry.The complex and unpredictable nature of the world caused Joe Ga to gradually change his goals...“Sir, how did you end up here?”“I don't know, I just wanted to make some money at first, buy a house, marry a wife. But slowly, as more and more people appeared around me, my goals started to change.”“So what are your goals now?”“Now, I just want to retire peacefully with my guys, really!”