When a male phallus of particular dimensions enter the women her opening while begin to secrete a concrete like substance while being penetrated to try to form the vaginal opening into a mold of sorts for that particular phallus. When phalluses of different dimensions enter the opening they the hardened substance is shattered or is cracked due to the force with which a smaller phallus is moved inside to compensate. The substance then is deposited as residue at the very opening of the vaginal cavity instead inside forcing the wallls apart and creating the dilapidated look.