How hard do your balls get during sex?

[NYguy]

Lately, for some reason my balls have been getting hard as hell during sex..i havn't got a clue why. Has this happened to anyone else?

They kinda move up really high and to the sides, feels like my sacks getting really tight. WTF is going on?...am i becoming BOS?

 

[Bench_It]

They're supposed too come up and your sac get tight. Means you're getting ready to blow your load.

 

[NYguy]

Ye i know, but this wasn't happening at all until recently.

Sometimes, its like they 'pop' up out of placee so it looks like they've dissapeared...

First time this happened i was like 'where the hells my left ball gone!?'