Anatomy of a Monster Girl

The changes that occurred to the monstrous species of our world after The Last Laugh were drastic, but despite each type of monster girl being utterly unique, there are aspects that (almost) all monster girls share.

Form
Monster girls are, obviously, girls of monstrous demeanor. While the monstrous features are all unique, the girl features are all quite the same, bearing a human face, head and upper body. The build of each species tends to be different, with smaller races such as Harpies being petite and larger races like Minotaurs being buxom.

Breasts
One of the most surprising commonalities among monster girls are their human breasts. Despite only mammalian species being meant to have breasts, all types of avian, reptile, insect and aquatic species have functioning breasts from which their newborns feed.

Vagina
With the exception of certain beastfolk races such as Centaurs and Lamia, all monster girls have human vaginas in the places where one would expect to find them. One incredible and unique aspect of monster girls is that they only ovulate on command instead of in a cycle. This way, they are capable of engaging in as much recreational sex as they please without worry and only settle down to start a family when they feel they are ready to. Given the amorous nature of monster girls, this is more than just a little convenient.

Behavior
Where most monsters were simplistic and bestial before their transformation, they are now all sapient and capable of human-levels of intelligence. While some retain their violent or dangerous natures, they have found it counterbalanced with a constant feeling of amorousness and a desire for love, partnership and sex. For this reason, almost no species of monster girl will ever kill a human. It should be noted that a monster girl being pacifistic does not mean it isn't dangerous.