Ah, cosplay, something misunderstood and beautiful. And if you don't know what it is I will explain it, I promise. But conventions have a small problem sometimes, and it involves consent or lack of it.
First, cosplay is the practice of portraying one's favorite character, or characters, in an accepting environment where others are doing the same. So, those people who are carrying around swords you think are dumb? They spent hours and even hundreds of dollars on them. These costumes are not cheap. And they go because they love the show, artist, actor, or any other aspect. It's art.
Where the problems come in are with how people think of the character or costume. Let's be honest: not all characters are modest. And that's fine! Power to anyone who wants to rock these characters, because, me being shy, I'm not confident enough to do this. But that does not mean you have the right to touch, grab, or do anything they don't want to them.
It's a character, and people commit, but they have every right to report you. This convention should be a place where they feel comfortable, even wearing less than others. For the sake of social and community peace: STOP. No one wants to be treated like eye candy or disrespected here. It's social and the experience of a lifetime.
So, please, show some respect. You can ask for pictures, compliment them appropriately, and be friendly. People even walk around with free hug signs. Just don't be a creep! This warning goes for everyone. If they say no, they mean no.
Thank you! From a friend of a cosplayer and general fan of media.