Kusushi No Hakushaku Reijou Wa Densetsu No Koryuu Ni Aisareru

It's the height of the Magical Era. The Daughter of a Countess, Fizz, who inherited the skills of the already obsolete profession of “doctor” from her foster mother one day finds a baby dragon whose parents had passed and decides to secretly take it in. The baby dragon, now named Kuelle, is the legendary Lune Fairy Dragon that can transform into a humanoid using various kinds of magic. Fizz works vigorously to raise this untamed child, but because of a scheme by her step-sister and fiance she is accused of murdering her fiance's father.