A twenty year old virgin. Someone who has reached the age of 20 without having penetrating sex (oral sex doesn't count as losing virginity).

The double 'x' is taken from the Roman numeral for 20. YOV is an acronym for "year old virgin". Perhaps originating from the film "40 year old Virgin" staring Steve Carell.

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