I've had funny encounters while in Touhou cosplay. All related to gender. FYI: I'm a straight male crossplayer.
Here are a few short stories.
Heading back to the con, I was walking down the street in my Keine cosplay with some fellow cosplayers after dinner, a car slowed down and some guy tried to get my attention from the car's rear passenger quarter:
"Hey! Hey! Can I have your number?"
"Excuse me, what?"
"Holy shit, you're a dude!" and the car sped off.
Did I just get hit on?
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In Sanae cosplay at a very small convention that I drove 10 hours to meet a friend, I was approached by two very timid young ladies.
"Excuse me...?"
"Yes?"
"Your costume, it's from Touhou, right?"
"Yes it is! I'm a shrine maiden."
"I told you!" "Okay you win both!"
"Both?" I ask.
"yourdressisveryprettybye!"
Kay, thanks!
(I'm assuming they were betting each other on what series my cosplay was from and what my gender is.)
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In Sanae cosplay but a different con, while I was sitting down playing a game in the game room with a friend. (A side scrolling shmup which we kept joking about was totally going the wrong way and stuff), a rather carefree and smiley guy is walking past me and suddenly leans over ans asks:
"Whoa hey are you a guy or a girl?"
"Yep!"
"*thumbs up*"
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On more than a few occasions I get this type of exchange:
"May/Can I take your picture?"
"Sure."
"Whoa! You're a guy?!"
"That I am, teehee~ *poses*"