coming from the perceptions you can get when stoned, the feeling that you are in a giant bubble (or a bubble of varying sizes, depending on the situation).
2. adj. phraze - describing a relationship between one or more individuals. If two people are said to be 'in the bubble' with each other, it means they have a certain connection, an understanding. they are on the level with each other.
the bubble is representative of mental connection, not simply sexual or romantic connection (though this may also exist in some cases).
dudeA: 'yo dave, you ok over there...?'
dudeB: 'yeah man, i'm in the bubble'
2. guy: so you girls are together? wanna 3some ?!
girls: erm... see it's like this: were in the bubble but you're on the outside, so its not going to work out.
guy: wtf... awwe.