After Being Picked up by the Eldest Lady, I Counterattacked by Slaying Dragons

After the dragon clan that destroyed the world disappeared, a large number of sub-dragon species still roamed the scorched earth. In the face of these genetically mutated dragon-blooded monsters, the power of technology has had little effect. Fortunately, humans have unearthed some kind of strange ancient alchemy product from the ruins, which is suspected to be able to resist the dragon... Against this background, Feichen traveled through time and fainted at the beginning and was picked up by a girl on the side of the road and brought home. She seems to have an ulterior motive...