Bartering Herself (Post-Apocalyptic Older Woman/Younger Man Erotica)
Sharon tries to cling to normality as the world falls apart around here. She waited at home for her husband until she was forced out of the house to find food and water.
Kyle was house sitting for his folks when the world fell apart. His dad had prepared for it to happen, but was caught away from home on vacation when things went bad.
Sharon collapses on Kyle's front lawn so he drags her inside to avoid attracting attention to his place. When she wakes up she discovers he has food and water, and lots of other useful things, but does he have a place for her? Despite being twice his age, when it comes down to it the only thing Sharon can offer him to let her stay is herself. Kyle isn't satisfied with just having her every now and again though, if she wants to stay he demands total control over when, where, and how.
This short story is approximately 6500 words and DRM free.
Erotica in a dystopian setting... well, just barely. The two characters don't actually have to endure too much. The mess outside is mostly alluded to rather than experienced. But to be honest, I don't read erotica for the setting. So it's a nice twist, but the main thing is STILL the main thing.