Nanya of the Butterflies — Barbara Hambly

A novelette of 14,000 words. In his quest for a wizard to teach him to use his powers, former mercenary captain Sun Wolf thinks he may have finally found one. Unfortunately, it looks like that one has summoned a dragon to destroy an innocent town - and it's the second dragon to afflict the town in two years. Yet the only wizard he finds there is an untaught - and very pretty - little hedge-witch who sells perfumes and illusions.