Giantess step-sister humiliates her step-brother with her big feet

Markétka is your older step-sister and she tormented you since you were little. She pushed you, she did hide your things and she also made you smell hes socks and put her big feet into your face. Now you're taller and bigger then her so she can't do those mean things anymore. But recently you have told some thing on her that should have stayed a secret and Markétka is really mad at you now. She had this potion that can turn anyone small as a bug in her reserve and this is the time she'll use it. On you! When you arrive home she gives you, what she calls a nice cold drink, but is really the tiny-bug potion and the second you drink it you start getting smaller and smaller until you're at Markétka's feet, small as a bug she could crush with her foot in a blink of an eye. And now, your punishment awaits! Markétka start to punish you and humiliate you using her huge smelly shoes and her BIG feet. Whenever you try to run she steps right in front of you, nearly crushing you.