Your girlfriend was cursed to become a dragon whenever under intense stress, pain, or when the moon is nearly or completely full. She was an uncontrollable beast, all instinct. With the vial, she’ll be humanoid & conscious, though, like her body, her mind will be much more attuned to that of a dragon: slightly primal, rough, quick tempered, a little arrogant, a bit of a brute, less controllable, but she’ll still be herself at the core and she still loves you. She doesn’t look half bad though.