Paddy and his new girlfriend are in the car together, on a dark winter's night, down a remote country lane.
The kissing and canoodling starts, and she asks, 'Paddy, do you fancy going on the back seat?'
'No!' he replies quickly, and the kissing and canoodling continues. Soon, the windows begin to steam up, and the girlfriend asks again, this time breathless with anticipation. 'Paddy, do you want to go on the back seat?'
'No!' he replies again. 'Not a chance!'
'Why not?' she asks, her feelings hurt, and not understanding what's going through his mind.
'I want to stay in the front with you,' he replies.