I was one of those people. The first convention I went to (also one of the first places I met my wife) I didn't change for two days before I had to sneak into the dorms to shower lest I lose my friends. I had gone to the convention on a whim a day early and didn't plan for any lodging. Luckily it was on a university campus (which I now attend) and I was able to get a few winks of shut eye in the back of the classrooms where they were playing anime all night long.
Have you ever heard of someone else meeting their wife at such a convention? That's pretty unique and pretty awesome! Were you stinky when you met her? How many days in to the convention? Ha.
I think it was the second day, and I don't think I was too smelly (though I proved to be a poor judge of my own smell). I was cosplaying L from Death Note (which is the easiest cosplay ever; long-sleeved white shirt, jeans, black hair, done!) and I found a Death Note tie on the ground that someone had dropped. When I met my friends later that day it turned out that she was the one who dropped it. We wouldn't start seeing each other regularly, though, until later that year when Halo 3 came out (which I sold to her) and she invited me to play it at her house.