Guardian of dragons

You won't believe it, but a long time ago, in ancient times, people were friends with none other than magical dragons! Unfortunately, this friendship did not last long... After the dark ages, dragons began to be caught, and after they were caught, they were imprisoned in deep dungeons, leaving them to be forgotten. However, a girl living in a distant fortress, Ping, manages to free the last surviving dragon, with whom she embarks on a long and dangerous journey to prevent the extinction of the entire dragon family.