When you are with a girl, probably a virgin who is very tight, or even if she just has a narrow vagina, you find that although this may be the case, you can quite nicely fit yourself in her. I.e. she has narrow margins.

Narrow margins on a page means you can fit more on it than usual. Applied to this, you can fit more in her than your usual.

Sometimes it is when a woman widens more than the average when she gets wet.
Gary "I was with a virgin last night Bob"

Bob "O really, how was she, did it suck because?"

Gary "No, luckily she had narrow margins"
by Gary ;)! October 30, 2009
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