Why do some girls sniff guys?

I've had a few girls in my time walk up and hug me and just take a sniff at the same time. Some are obvious, some try and hide it. I shower often and wear deodorant but I consider myself quite musky if you get me. They always say I smell good but I find it odd. So why sniff a guy?
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+1 y
Sometimes I even get sniffed after excerise again still not in a bad way. Just a bit confused really what's the purpose and the gain?
Why do some girls sniff guys?
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