A sex act involving forceful, anal sex where the male is on top with the female's knees placed beside the ears. The force of the thrusting pushes the female along the floor/bed/sex platform using the lubrication produced to slide her along on her back. The streak lends to the "smear" terminology, the color of the naturally produced lubricant lending the "Cuban".
I saw a Porno last night where some hung dude ran a 100 yard "Cuban smear campaign." on a drunk bitch.