When one thinks of being intimate with someone, one might think cleanliness is a good thing, you’d want to be fresh and clean for your lover and even be mortified if you were considered in any way unclean. Some however enjoy the dirt, the grime, the smells. Dirty feet always strike me as so not sexy in any way, but to some they are very appealing. Ones want to lick the dirt off. I like being barefoot all the time when I’m home, so I’m a bit used to not having the most clean of feet, not as bad as in the pic, but not kissably clean.
To some, that is certainly no deterrent to getting close, they even want it. Dirty feet going up and down your cock, under your ass cheeks pulling you deeper inside, maybe even leaving smudges on your backside as they graze over your ass. Dirty feet on your face. Sometimes blacks on racial humiliation calls will mention their owner having dirty feet they are being made to lick and suck clean, perhaps feet are a humiliating thing to have all over your face, so it falls in line with their need to be ground into the dirt and treated as sub humans, licking between the toes and cleaning them.
Dirty shoes also often make an appearance in some fantasies. Ones caked in mud and dirt. Some cultures, like Arab, will throw shoes at people as an ultimate insult, as they are considered unclean. Many with sexual fetishes are attracted to things ones would consider unclean, like anal. As gross as most feet are, I’d still rather lick a clean foot than a clean ass.