Warning: Blanket statement Cos-players are inherently freaky people. See, the whole concept of showing admiration for a character by dressing up like them is inherently flawed simply because cartoons can get away with significantly more abstract clothing. For example, there was this girl walking around at Otakon in a black bikini, black heels, and a black tail stapled onto her bikini bottom. This was apparently a costume designed to look like a specific character. But when it's worn by a jail-bait 16 year old in a convention full of awkward guys, it just becoms 1 1/2 square feet of bad idea.
My favorite, though, was Jon dressing up as Ruroni Kenshin. Kenshin is a male character, but since most of the cos-players who dress up as Kenshin are female, most people just assume "kenshin cos-player = chick in drag." Heather (who also dressed up as Kenshin) was angry because the Otakon staff wouldn't allow her to keep her costume swords. Demonstrating this, she pointed at Jon and said "Look, they let her keep her swords!"