Mark eagerly switched to my other foot and this time as he licked I could hear small moaning sounds coming from him.

"Oh you like licking your sister's feet do you?"

"Yes." He whispered just before sucking my big toe into his mouth.

"Then I think you should thank me for letting you."

With no hesitation Mark looked me in the eye;

"Thank you for letting me lick your sexy feet Megan."

"Stand up and rub your cock on them."

Mark stood and grabbing his dripping dick started smearing his pre cum all over the bottom of my feet, moaning the entire time.

"Now go back and lick it off."...