Intercourse preformed under no consideration of any possible consequences (usually preformed by males)

Overweight

Unattractive
Ex's

Married
Best friends
Best friends partner

(one does not have to shout Yolo before, during, or after for it to be considered Yolo sex. One must simply just not care)

Large, beautiful breasts that are keep well consealed and initially appear to be much smaller and less impressive than they actually are until unleashed.