Fingering a girl's pussy, then taking a whiff of your finger. This helps determine if you want to put your head in between her legs or not.
If you don't do this, and just shoot right down for the pussy... what happens when you get down there, get here expectations up, and then you realize she smells rotten, and your eyes start to water. Do you stop? Can you? Do you tell her that her pussy stinks to high hell and you aren't going to be able to eat it?
Avoid uncomfortable situations... Know what you'll be eating before you dive.
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