It was known to the kidnappers that Diamond Tiara and Silver Spoon came from rich families and therefore be perfect targets for ransom.
 
And of course while there was no desire to hurt the two young adults the situation did call for some sort of “Peril” to be added to give their families the pressure of time.
 
And so we have Poor DT and SS; squirming, squeaking, and moaning as their feet are pampered by smooth, automated, and nimble hands. Oiled by an illegal magically infused sensitization gel that if left unchecked will ensure their soles and toes remain sensitive, and maybe even grow an extra shoe size.
 
Will their families be able to pay up in time? Or will these two earth ponies find release weeks later with a new found desire to keep their sensitive feet exposed as all their expensive heels and pumps no longer fit.