When you impregnate a girl, do not stay around to be a father figure and do not pay for child support.
Dude, I think my condom broke when I was having sex with Molly Last night.
Do you think she's pregnant?
I don't know, but if she is I'm going to let her keep the change.
When you offer your friend a joint and they are allowed to smoke the rest of it.
“Hey can I hit that?”
“Sure! Keep the change”
“thanks bro!”
Receiving sexual favours as a surprise reward for some assistance you've given to someone.
"I helped Cheryl move last weekend, and after it was done, wham-bam-thank-you-ma'am, and keep the change, baby!"
Giving someone a hummer and swallowing the "deposit"
All the guys liked her because she was known for keeping the change.
the ultimate conclusion to fellatio is to hmmm... to swallow the ejaculate would be the correct terminology...
johnny: last night was great... the first thing she did when i walked thru the door was go down on me!! i am one lucky bastard...
rod: awesome... did she keep the change?
The action of swallowing a man's ejaculatory fluids intentionally, as opposed to the "change slipper".
When she moaned as she ate my pre-cum I was convinced that she would keep the change!
The act of swallowing a man's cum
I shot my load in her mouth and found out she keeps the change.