No sweat off my balls.
No problem for me. No big deal to me.
Sobody you don't give a shit about doesn't invite you to their wedding. Your response: No sweat off my balls.
sweating my balls
If somebody desires physical interaction of a sexual nature with you, they are sweating your balls.
"See that chick over there? She's totally sweating my balls"
No sweat on my balls
Can easily do something
I can dunk on you with no sweat on my balls