Sixty-nine is the only dinner for two
It does take two people to 69…
Though the line is crude on the surface, it completes the train of thought CG has been following from the start of the song, i.e. the only real relationships people have are sexual.
The act of 69 requires the two sexual partners to orally pleasure the other simultaneously. This comment may lament the fact that he no longer has meaningful dates and the only dinner for two he’s getting is 69.
This line may also mean that the sexual position 69 is the only time that both parties are REALLY on an even playing field, i.e., other times in a relationship one is usually sacrificing or compromising for the other.
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