I HATE being tickled cuz I'm really really ticklish.
My girlfriend likes it.. not crazy rough rib puncturing tickles, but light ones.
And my favorite place to tickle her is lightly on her inner thigh... it drives her crazy and turns her on easily. Also a slight tickle on her neck with my lips and stubbles would do the trick
If i just wanna annoy her and have some personal fun lol.. I hold her leg and tickle the bottom of her foot! haha