During the war against Sukebe, some people found that they could make Pokégirls loyal to a single person and this knowledge spread. A person who did this was called a Tamer. Pokégirls now act as a human's friend/slave/partner/whatever.
There are two categories of Pokégirls, Domestic and Feralborn. Feralborn Pokégirls are birthed, usually by parthenogenesis, by Pokégirls who have themselves gone Feral. Since they spend their formative years living like wild beasts, they are very animalistic in thought and possess strong powers. Domestic Pokégirls are ones that were either born in a Breeder's farm or were a human female that underwent Threshold.
Domestic Pokégirls normally have less power than a Feralborn one, but will possess more intelligence. It is possible to increase a Feralborn Pokégirl's intelligence, but most Tamers consider this is a waste of time when they could be enhancing their combative skills.
All Pokégirls have a lifespan equal to that of humans, save those with the Longevity enhancement. Pokégirls with the Longevity enhancement can live for centuries. They undergo their first puberty normally, but only undergo their second one when they reach middle age for them, which can take hundreds of years.
Pokégirls all have strong desires to have sex, to a greater or lesser degree depending on the specific type of Pokégirl, but these hormones only kick in during their first puberty, which happens around the same time a human girl would undergo maturity. Pokégirls are infertile as far as normal reproduction goes, being able to bear young only from parthenogenesis.
"Whilst some tamers are forward enough to tame their Pokégirls in public, most are at least modest enough to keep it in the bedroom."