Lyric discussion by BackofYourHead 

The song details a pickup leading to a one night stand. Two people making idle chat leading to a night together. They both make small talk which really doesn't matter since they both know where it's leading.

"We come and we go" is a double entendre if you think of it in a sexual context with a one night stand. Which is why it's the thing he keeps in the back of his head.

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