I've typed summarized PokeDex information that'll be used on my FanFic. I have some for Nidorina (other Pokemon have more explanations on how it would act if it were a real animal):
Nidorina:Growing up is different for a grown Nidorina; it has bigger spines, it has sharper claws, and pointed teeth. Very social, Nidorina exists in small groups. It will not attack unless it is disturbed by clawing and biting at the foe. It rarely uses its spines but injects a deadly poison. It carves out a nest once a year to bear young in the ground near tree trunks. Nidorina becomes horribly aggressive when it is guarding its young from other Pokémon.
Nidorina's main horns aren't on her back but they are her spines. The Nidorina doesn't have a fully-developed horn, only a bump mark where the horn should've been.