How many more? And then what's he going to use on my poor bottom ?

It really was so unfair. They had chosen the pub carefully because it was discrete. How could they possibly have guessed that the pastor would walk in (with his horrid little dog) just as they had settled down at a table with their vodka and tonics. As soon as their eyes met and he gave them a curt, unwelcoming nod as he left a pile of pamphlets on the bar, they knew they were in trouble.

Their parents were strict teetotalers and members of an austere church. Although the girls were old enough to drink, they had been strictly forbidden to do so, and entering a pub was considered tantamount to heresy. But they were young and full of spirit (and sometimes 'spirits') and the risk had seemed worth it.
Now they regretted that decision: they were for it, and the moment had arrived.

Their father had stopped spanking them when they became teenagers: their mother (and the pastor) considered it inappropriate for a male to see their developing bodies. So hidings were now the exclusive preserve of their mother - and what hidings they were!
The formula was always the same. Once the crime had been discovered they were sent to their rooms and told to undress: embarrassing nakedness was part of the punishment. Their mother would go upstairs and re-arrange some of the furniture, notably the stool over which they would be required to lie. Then she would fetch that dreaded leather strap, actually an old razor strop. It was long and heavy, marked with the patina of years, first from sharpening steel blades and now from its more painful function. 

Then they would be summoned. They would make their way reluctantly from their rooms to where their mother was waiting beside the stool, tapping the strap against her palm. The elder sister would go first, laying herself across the stool, hands and toes on the floor, bottom lifted up. The younger girl would stand in front of her. 

The lashes would begin: one for each year of their  age, nineteen for the elder girl, eighteen for the younger. After a few strokes, the sting would be unbearable.

It was all so unfair.

Bottoms Up