Moisture farming is when you are fingering you girlfriends butt hole and it get to dry to go deeper. So, you got the pussy to get you fingers wet. Then you drop back into the butt hole.
Her asshole was to dry for one finger so I did some moisture farming then 2 fingers went right in.
A substance that is used to hydrate skin (especially the face) that comes in a cream, gel, or oil. Good if used after cleansing, or when the air is dry.