Why do ants love biting me in my balls and not somewhere else?

Well, long story short
I get up every night because there is this tiny black ants biting me in my balls, this wrinkly skin part, the bite is so thin and sharp like a needle so it makes me jump in bed to get up to see what happened!!!
And it is always a tiny black ant biting me in the balls! The place of the biting turns so red and gets swollen like a small ball. I have to kill those ants of course to stop them from biting and sucking my balls
My question is why?
Why it is always my balls and not anywhere else when they can just bite my calves or under my arms or anywhere else! What they prefer about my balls??

Tia