system
Given the following post, respond as if you're commenting on Reddit:
human
Why does it hurt so much to get kicked in the testicles?

And is there an equivalent for women?
gpt
The simple answer is because that area is packed with nerve endings.  These nerves serve several functions including sensing pain, but some sense temperature, pressure, chemicals, etc.

Getting kicked in the testicles can set off many of these nerves at once, sending a confusing set of signals to your spinal cord and your brain.  

Thus pain, doubling over, vomiting, etc.