Toe sucking and foot licking is a common way of expressing foot fetishism.

Foot fetishism has been defined as a pronounced sexual interest in feet. Extensions of this fetish include shoes and tickling. Sigmund Freud considered foot binding as a form of fetishism.[4] For a foot fetishist, points of attraction include the shape and size of feet and toes (e.g., long toes, short toes, painted toenails, high arches, soles etc.), jewelry (e.g., toe rings, anklets, etc.), treatments (such as massaging, washing partner's feet or painting partner's toenails), state of dress (barefoot, flip flops, sandals, high heels, hosiery, socked feet, etc.), odor and/or sensory interaction (e.g., rubbing the foot, tickling, smelling, kissing, biting, licking, sucking toes, rubbing genitals on foot, etc