Plain nasty? WTF with your dick between her soles? I would hope you would make sure are clean? I like to lick/suck on feet/toes I certainly don't consider it nasty (if her feet are clean). Almost all enjoy it, but some are mroe ticklish than others. Personally, I've never gotten a foot job (FJ). Maybe some day I'll try, but there are other things I lke to put Jr in more (like mouth, pussy, and sometimes the real nasty: the rear door).
I'd also wonder if a provider or stripper would do a FJ at the price of a hand job. Should not be different and risks of STD is same as hand job (very low).
But it is nice to hear from another foot fetish guy even though its a different area. I like just the visual look of woman's feet with nicely painted toes and have a little oral fixation with them