Meeting online people in real life is a very odd thing. Heck, even seeing someones picture or hearing their voice is strange enough if you had no prior knowledge of how a person you've been interacting with looks/sounds, as it's often much different then you would expect.
A couple years back I was a guest on the Final Fantasy Union podcast for their Trivia segment. I got a few online buddies from Final Fantasy Radio to listen and they were like "You sound so... normal." Like they were disappointed. Weird.
I had something like that once. "You look much cuter than I thought you would!" "I never thought I'd say this, but... cute picture!"
I'm not sure what people were expecting...
And this other time, people thought I was a dude, and after posting my picture someone still thought I was a dude. Do dudes have cute white bangs framing their androgynous face? Okay, no wait, don't answer that.
Anyway, I have an important question: Do I look like a minor? I've been asked for ID way too many times the past few years.

Personally, I think I look a bit younger than I actually am, but I definitely look over 20, and not in a 'a mature looking 17-year-old' kind of way.