I know one lad who ended up in the back of a car with a girl
Things were getting hot and heavy, they go to get down to it, and as it's bloody dark, he's operating entirely on touch (whilst also being off his tits).

He finds an opening, and advances with his spam javelin, only to be stopped after a few seconds. Turns out he's missed her 'entrance' entirely, and was currently humping between her leg, and the car seat.
( Agnostic Antichrist Baltimora, Mon 6 Dec 2010, 15:02, 2 replies, latest was 15 years ago)

urban legend is legendary

( Kitty v1.0 desperately naive, Mon 6 Dec 2010, 15:05, Reply)

However, my friend Ian did genuinely manage to fall into a roadside ditch
when he and his girlfriend decided to move their heavy petting session into the back seat and his trousers fell down, tripping him up.
(Cave Duck, Mon 6 Dec 2010, 15:12, Reply)

This I can believe
my life is a bit slapstick sometimes.
( Kitty v1.0 desperately naive, Mon 6 Dec 2010, 15:21, Reply)

You say that
but this has kind of happened to me. Not in a car though - I was drunk and he was very drunk, and it all went a bit wrong.
(berk, Mon 6 Dec 2010, 15:16, Reply)

my bf once failed to realise i was still wearing tights
took me about 0.05 seconds to correct him.
( rachelswipe with a fork, Mon 6 Dec 2010, 15:21, Reply)

Did it make your toes curl?

(Cave Duck, Mon 6 Dec 2010, 15:24, Reply)

POTD!
Well executed, funny and simple. 10/10
( sporters I’m sincerely gratitude to you, Mon 6 Dec 2010, 15:25, Reply)

Excellent

( Monty Boyce, My cheese game is strong, Mon 6 Dec 2010, 15:34, Reply)

Didn't realise it was an urban legend
But in the case of the above, it's true!
( Agnostic Antichrist Baltimora, Mon 6 Dec 2010, 15:20, Reply)

Car sex?
A good friend had a Triumph Spitfire which wasn't really any good for back seat sex. As a result he used to have sex with his girlfriend across the seats with the passenger door open. On one such adventure they were going at it so energetically on muddy ground that the car was shunted sideways into a slight dip. The passenger door slammed shut on his legs fracturing his shin. Mobile phones were uncommon in those days so he had to drive his girlfriend home then go to hospital.
(porkylips looks better as the sun goes down., Mon 6 Dec 2010, 16:07, Reply)