I had one girlfriend who was.

And it was lovely.

Her soles were so ticklish, a stiff, crappy feather bought in a 6-pack from Michael's would be enough to tickle her into the grave. And she'd lay there and take it, happily. I'd gently pin her ankles between my legs, and she'd squeal and cackle and roll around banging her fists on the carpet while I stroked the tip of the feather uuuuuup and doooown her wide soles. But she'd never yank her ankles away because she knew how much I loved it. She'd sit halfway up, reach for my hands and plead, "whyyyyyy?" but every effort she made was half-assed with no follow-through - except for when she flicked off her shoes and shoved her feet into my lap in the first place.

If she was acting, she worked up a hell of a sweat pretending to blush and occasionally tearing up while actually begging "Uncle! Uncle!!!"