Tonight, she was supposed to be his escape. Hotel room downtown. King-sized bed. A bottle of something sparkling waiting in an ice bucket. But 9 p.m. came and went. Then 10. Then 11.

His name was Marcus. Married. Two kids. A house with a porch swing and a dog named Otis. Gina had met him at a gallery opening—he’d complimented her boots, she’d made fun of his tie, and by midnight they were sharing a cigarette in the alley behind the venue.

Here’s a short story inspired by the title and mood you suggested—blending confession, desire, and the tension of a hidden life. Confessions of a Side Piece

That was eighteen months ago.

But tonight, she let herself feel the sting of being second place—and wrote it down anyway.