The phrase "natural lubrication" refers to the moisture that a person's body naturally produces during certain activities, often during sexual intercourse. It helps make movement smoother and more comfortable. Full definition
For the really good news, applying lube can actually increase your chances of producing natural lubrication again — fake it «til you make it! (womenshealthandfitness.com.au)
Decreases muscle cramps: Water is the body's natural lubrication system. (naturallysavvy.com)
Similarly, when you and your sexy singles partner engage in sex, the body produces natural lubrication so you and your matchmaker partner do not have trouble with excessive friction. (adultfindout.com)