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There was something about being able to talk to another person that way, without filter or fear. It was the thing – one of the things, at any rate – that had drawn her to Gary, this idea that one could just speak to another person without a neat framing of thought. She could just open her mouth and let the thoughts spill, and he would accept them in his Gary-way. Still did.

So why supplement?

There was just something about one on the side. It had always been that way for her, though she had never cheated on Gary, never even kissed another since they first got together. For her, on the side meant someone who could occupy her thoughts obsessively in the fallow times. A fallback, you might say. A temporary substitute. A side dish of sorts, something to complement but not replace the main course.