One who inserts their fingers into an unwashed vagina (human or animal) and then proceeds to use butter instead of lubricant.
Harvey: I really fancy a fish finger sandwich.
Felix: Okay, just be quick about it.
Harvey: Okay i'll fetch the butter while you spread your legs.
Felix: I'll think you'll find that a pussy cannot spread their legs.
Harvey: Ahhh ease up.
The most heinous sexual act. So terrible that your friends can never speak to the girl you gave it to ever again. In addition, they are not allowed to be friends with you for a month. At the end of that month you'll still think it was worth it.
A Uk police car, specifically the kind with an orange strip all the way round the sides. A bit of a misnomer really, but marmalade sandwich just doesn't sound right. Plus these days most police cars are either in high visibilty markings that resemble batenburg cake, or just plain white.
The "Chicken Sandwich" is when two great things meet eachother at the peak of mental and physical pleasure. A man is bending a supremely gorgeous woman, doggystyle of course, and he realizes that he is hungry. This is where the chicken sandwich comes into play. While holding the chick's ass in one hand the man simultaneously eats the chicken sandwich with his right hand, thus bringing together two joys that every man craves.