I've had a very similar experience at Anime Vegas 2011. There was a wedding reception going on where most people did their cosplay gatherings. People were loud and said rude things because there was a wedding going on in their spot. The bride and the guests did not take it sitting down either, and most of them made fun of the cosplayers.

It's their special day, you weren't invited, go away. Yelling about yaoi and buttsex while they exchange their vows is the most disrespectful thing I have ever seen.

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