No complaining folks.

Researchers have long known that male bat bugs ignore females’ conventional parts and instead use their sharp penises to stab the females’ abdomens, injecting sperm directly into the bloodstream.

So the females evolved a defense: structures called paragenitals that guide a male’s needle-like member into a spongy reservoir of immune cells.

But the females aren’t the only ones in need of protection. Observers documented males performing the same injurious sexual acts on other males.

Now evolutionary biologist Klaus Reinhardt of the University of Sheffield in England has discovered that male bat bugs have developed their own versions of female paragenitals to avoid the assaults.

And some female bat bugs are mimicking the paragenitals of the more successful males to improve their defenses.