Bill Anderson : Bill wears boat shoes. Either enclosed or, more often, sandals like birkenstocks. Because of this he has a slight sandal tan. He mostly wears light colored shoes, in beiges or pale blues to go with the color scheme of his house/Sootopolis in general. His feet are insanely clean, and completely hairless. Whether this is genetic, or due to cosmetic surgery/waxing is unknown. You would need to survey Lars/Claude for more information.
While he doesn't enjoy the feel of grass between his toes, he HAS had blood between his toes on several occasions. One one memorable occasion, his own. His skin is soft, and you get the feeling that he uses salt scrubs exactly as often as advised on the package.

Zac Ramsay : Zac often goes barefoot, so his feet have plenty of solid calluses and sometimes grass stains. Since he became Avatar this tendency to forego shoes has become more common, as he can heal his body at will. His feet are hairy, but as he uses scented soles for his boots there is a lingering scent of Oran berry between his toes. Like Rowan, Zac knows the subtle and alluring tickle of having seed germinate and grow between his toes, though he has never had this happen while wearing socks.
His foot size is proportional to his

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cheer.