When someone wants to ask someone out, you put "the balls in the pants". Mostly used for girls who want to ask out a guy. Can also be used for a guy who has been longing for a girl for a long time but doesn't have the balls to confess.
Variations can be just saying the phrase, or putting super balls in each pocket to give you courage.
Jocelyn: I really really really like him but I can't tell him. What if he says no? What should I do.
Jasmine: I think it's time for you to put the ballsin the pants.
The act of pleasuring a man while his pants are still on. Hence "over the pants" it's generally very difficult to master as the penis is hard to get to. You're better off to take his bottoms off and just give him an actual hand job. It's more pleasurable.