Gurgle.

At first, it was just a hesitation—a tiny pool of water that lingered around your ankles while you rinsed your hair. You ignored it. Then it became a shallow lake by the time you finished conditioning. Finally, it became a swamp: standing water, gray and slick with the ghosts of soap scum, hair, and the quiet erosion of neglect.

Then, you poured the baking soda down the dark throat of the drain. It snowed into the abyss. You followed it with the vinegar.