Mar 31

How can I ask a girl if I can lick her feet?

I would be a slave. I love femdom.
I would massage, kiss and lick a Mistress’s feet.
But.. how can I ask to be her slave? Or.. how can I know if a girl would allow me to do it? I can’t simply tell "Can I be your slave and link your foot?" ..please help me! I really need it.
PS: I should ask it to a 13-20 years old girl.
I’m Italian and I posted a reason in Italian’s Yahoo! Answers. Now i post it here too, translated.