When someone(generally a female)'s stomach sticks out farther than their breasts. Comes from the fraise "Bitch's stomach hang out farther than her BOOBs DO"
"Nah dude. Let that chick keep walkin, she got the MAD boob do"
Take 1 erect penis and 1 pair of breasts, slide erect penis between breasts, get owner of breasts to lean forward to enjoy the end of the penis. From her point of view it's like a hot dog. Voila - Boob Dog.
Last night was crazy, my girlfriend and I made a Boob Dog, I don't think she liked the manaise sauce it came with...
A douche boob is a person who is not quite a douche bag, however, at the moment they deserve some kind of name calling. Douche rack for plural.
Tim: Whoa! He just spilled his drank all over her.
Adam: What a douche boob! HEY! YOU ARE A DOUCHE BOOB!
Tim: Ya, but he definitely is not a douche bag.