Dragon & Company are Go!

The evil dragon who was the enemy of humans turns into a helper after several thousand years!? That was a story of the past, when magic was still a fundamental part of the world. At the end of a battle with the Hero, the strongest dragon was sealed along with his allies. The name of that dragon who ruled over vast races of magical beasts was Nielfeld. And several thousand years later—what he finds after the seal was broken by the descendant of the Hero, Patricia, was a world where magic had fallen out of use and science dominates! Introduced to the human society by Patricia, Nielfeld and his allies helps the humans out from the shadows!? Source: Hobby Japan