Not so much odd just one i've never heard of.
Although, thinking about it, it is a bit odd.
I mean I can understand most kinks but smelling someone just never struck me as ... erotic.
Well, the smell of sex, among other things, do make people horny, so I guess it's a more extreme version of that? Or maybe it's just that "wrong" or "dirty" thing that people like.
Everyone! It is time for Devilbird's Fetish corner; where we delve into some of the reasoning behind certain obscure fetishes. There are a few reasons off the top of my head that people can develop a smell fetish.
First: Typical fetish development. Fetishes tend to crop up after something related has a noticeable impact on one's life. In the case of this particular fetish, an example could be that someone with a strong sense of smell unable to escape strong smells of body odor. They may resent it, but it leaves an impact on the brain. Thus when sex starts to get involved, and they start to smell the sweat and sexual fluids of their partner, their mind latches the thought of strong smell with the thought of pleasure.
Second: Pheromones. Smell fetishes typically (but I am hesitant to say always) revolve around the body odor of their partner. It isn't really just getting off onto stinky things. Part of this is due to a person's sweat and bodily fluids containing the same pheromones that we use to naturally be attractive. While the smell may not be pleasant to everyone, it still contains a stronger concentration of those pheromones the more a person sweats. A person could simply be easily affected by them, so they smell that accompanies is more of a side product rather than the main appeal at first. Then, as before, they start to associate smell and pleasure.