Just a little idea I've had kicking around in my head and seeing if anyone else is interested.
Basic Concept is a Monster Invasion has kicked up.
It starts with an Alpha version of a monster who, among other properties, rapes human women. The women that have been raped by the Alpha always get pregnant and experience accelerated pregnancies that result in the births of Beta versions of the Monster. These Betas mature quickly after birth into weaker versions of the Alpha monster, and soon are raping women on their own.
Women who've been raped by Betas usually, not always but usually, also become pregnant. The women raped and impregnated by Betas also experience accelerated pregnancies, if not as accelerated as the victims of the Alpha, that result in quickly maturing Gamma versions of the Alpha Monster.
Mature Gamma monsters also rape human women, the victims become pregnant more often then not, the impregnated victims also experience sped up pregnancies if not to the same degree as the previous, and give birth to an even weaker generation of the Alpha monster, etc.
Details of the monster can vary. Right now I'm picturing basically Bigfoot with bigger teeth but we can talk about that. This is to see if anyone is interested.