It could mean many different things. Here's a list.
-Stop talking, rip my clothes off and lets do it.
-He's boring me, I wish he would touch me right where I'm touching.
-I want to have sex.
-My leg is really hurting, I hope he doesn't want to have sex
-I have a rash under here some where I hope he doesn't see it
-My leg is really itching
-My skin is really dry, I need lotion
-I want him to rub my inner thigh
-I want him to kiss my inner thigh
-I really like him but I don't want to make the first move
-I'm really horny
-I'm not horny but I know he is so I will just try and make myself
-I'm bored and I just need something to do with my hand
Or maybe you should just ask her, it could be none of the above.