In the Backseat

Sex in the back seat is cozy and comfortable - or maybe just cozy, depending on how small your car is. At any rate, the backseat offers you room to stretch out and steam up the windows.
 

69

Simultaneous oral sex. Both partners lay across the backseat, the woman on the bottom with legs spread and the man on all fours over her in the 69 position. He eats her out while she sucks him off. We recommend that you lay down a towel first, or keep some tissues handy as this can get messy.
 

Up and At 'Em

Woman lays across the back seat with the man on top between her legs. She brings her knees up toward her chest. He kneels between her legs and pulls her pelvis up toward his. The woman can plant her feet on the interior of the car and use her legs to pump her pelvis. Alternately, if there is room, she can hook her legs over his shoulders. This position allows for really deep penetration, so go easy at first.
 

Cowgirl

The man lays across the back seat and the woman kneels straddling him. She should lean forward to avoid bumping her head on the roof as she rides his cock. This also allows her to vary the angle of penetration for better clitoral and G-spot stimulation.