Basically, if you’re going to a con and you’re gonna dress up, you shouldn’t worry about “obscure” so much since first of all, what you like probably isn’t that obscure. This is fuckin’ 2013 and the internet is a thing. Whatever anime/comic book/movie/tv series/whatever you enjoy is probably not going to be so obscure under the lens of a convention full of losers. Enforcing standards for cosplay that are far beyond common decency, basic quality, and good manners toward others is practically elitist and has no place with something that is glorified Halloween costumes.
I have a lot of thoughts on “nerd culture”, it’s connections with pop culture, elitism, and what comes out of that, but I ain’t bringing that up here. What I’m saying is that even if you don’t know what the fuck its from, if it’s a good cosplay, you can appreciate it.
Good example: I know next to nothing about Umineko except that my friend Bateman and his friends really like the series. It’s a visual novel thing I THINK and it’s about witches. Maybe. But I saw a really, really, REALLY good cosplay of like, Beatrice or something the last con I was at. If she wasn’t waiting in line for a big con event and I wasn’t on my way to something else I would’ve asked her for a picture because that was a good costume. I know vaguely what it’s from, I know next to nothing about the series or character, but that doesn’t stop me from appreciating it. If you are so far up your ass that you need to know everything about what every cosplay you see is from, then you don’t belong at a convention.