a sloppy reuben is where you put your dick between two pieces of marble rye bread along with sauerkraut and swiss cheese, and start to jerk off, when youre about to finish you take it to your woman and say "here honey i made you a sloppy reuben" and when she goes "what's a sloppy reuben", you say "here, take a bite!", when she goes to take a bite you ejaculate into her mouth and say "thats a sloppy reuben, bitch!"
Mephisto: "Man, my girl eats all the time, last night she kept asking me to make her a damn sandwich."
Gman: "Did you make her a sandwich?"
Mephisto: "I sure did! A Sloppy Reuben!"