You meet Ben at a bar not far from Chinatown. It's quiet at this time of day, and he's all alone when you waltz in ten minutes late. "Hey, dude!" Happy birthday!"
He smiles. "Thanks, Darren. I thought I'd never turn 21. Do you want to buy me my first legal drink?"
You agree, and soon the two of you have imbibed more than a little. "Well," you say, "I got you a little something." You reach into your bag and pull out the jar of weird goop. The label is very cool looking, but it's written in Chinese characters.
"What is it?" he asks, smiling.
"Uh, I don't know. The guy said it could be sexual. I thought it was high time you got some pussy!"
Ben frowns and opens the jar slowly. He takes a sniff of the ointment (which smells pretty nice) and begins rubbing his finger idly in it. "Look, Darren, I thought you knew, but I might as well tell you and start my 21st year right."
"What is it, man?"
"Look, the thing is, I'm gay. I don't want any pussy, so you can stop teasing me about it." He looks sad and defensive. You are stunned. It's true that he has never seemed interested in girls, but you just thought he was shy. Ben is a big, well-muscled athlete who seems as butch as can be.
As he is talking, he absently rubs some of the ointment into his hands. He is clearly waiting for you to react to his news.