A double bubble is where you just can't stop farting and burping at the same time. This is very often caused through eating spicy food and drinking lots of gassy larger.
I had a brilliant Indian last night followed by five pints of lager. When I got home I just couldn't stop burping and farting. It was the worst double bubble I'd had for ages.
A characteristic of obese people, especially women, where their excess fat creates a protrusion in the front as large as (or larger than) their posterior, hence the "double bubble".
When playing spades casino or any card game. When the team Or player reaches two games before you get one, that is considered a double bubble. In most circumstances this ends the series and doubles your points.
(1) When a girl has both a big chest(Breasts) and big posterior(butt).
(2) When a guy eats a girl out and makes a wet pop.
(3) When a guy goes back in twice or orgasms twice inside a girl.