Invisibility Potion 2

Dexter's mother was on the way to the bathroom, to take her morning shower, when she felt someone grab her from behind.  Her tight tank-top was lifted over her juicy, soft, and fat ass.  She looked down to see her thigh thighs spread below her pussy, as if an invisible cock was forcing it's way through her legs.  Her top was ripped down, exposing her exquisite tits.  The fun was just beginning, for our invisibility potion weilding teenager.