Förutom den medeltida aspekten kan detta vara Robin McKinleys Dragonhaven
Jake lives with his scientist father at the Makepeace Institute of Integrated Dragon Studies in Smokehill National Park. Smokehill is home to about two hundred of the few remaining Draco australiensis, which is extinct in the wild.
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On Jake’s first overnight solo in the park, he meets a dragon—the thing that he would have said he wanted above everything else in the world. But this dragon is dying—dying next to the human she has killed. Jake knowns this news could destroy Smokehill. The dead man is clearly a poacher who attacked first, but that will be lost in the outcry against dragons. But then Jake notices something even more urgent: the dragon has just given birth, and one of the babies is still alive…