George R.R. Martin definitely has a foot fetish. In the books, there are plenty of lush descriptions of beautiful females showing off their feet, and of men finding them attractive for that reason. Sandals seem also to be the standard form of footwear for women in southern locations such as Dorne and the Dothraki sea. Daenerys is described as wearing beautifully intricate silver or gold sandals on various occasions. I do not want to get too detailed in order to avoid spoiling anything.
As for tickling references, there is naturally The Tickler, a member of Gregor Clegane's band of psychos. There is no actual tickling being performed by anyone, but I remember that when Asha Greyjoy takes a lover, there is a scene when he briefly tickles her while verbally teasing her. Or maybe it was the other way around. If anything, it was cute foreplay, nothing more, so the passage did not stick into my memory.
If you like the setting, Briel7 made a few nice drawings. You can check his deviantART if you like,
http://briel7.deviantart.com/gallery/ but here is also one that features Cersei being punished by the Sisters of the Seven:
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