It's a god start, but can we get some description as to what the girls look like? some description of the torture aside from stroking? It's a nice sketch, but it's hard to visualize aside from the little bits of detail. Personally, I'm a foot person, what do they look like in your mind? (pictures won't help me, sorry to say). But it's not bad, but more description for visualization purposes would be nice. It's hard to strike the balance between good descriptors and scenes of tickling, or really any physical situation like tickling (erotica in general comes to mind).
keep going, I hope this helps as just a note to...well, help. PM me if you have questions I love to write and really should post something, I'm just afraid to have it sound like another tickling story.
Dave