The wet slap of skin on skin hit me the second I shoved the apartment door open.

Not the soft, lazy kind Mike and I used to make on Sunday mornings when he still pretended to love me. This was filthy. Hard. Greedy. The thick, rhythmic smack-smack-smack of a cock driving deep into a cunt that was already dripping. Moans poured down the hallway—high, breathy, shameless. Laura’s voice. My stepsister’s voice. The same mouth that used to steal my lipstick was now begging my boyfriend to fuck her harder.

“Yes—fuck—Mike—fill me up—”

My keys slipped from my fingers and hit the floor. I didn’t pick them up. My legs carried...