Well, maybe it's the wording, but it was kind of confusing to me, too.
Why are you looking to see how teenage girls are looking at you?
LOL. Yeah, my crappy use of the English language leaves a lot of people confused... Sorry, I'll try again...
When I dress male, I think I'm sufficiently boyish enough that people believe I'm an actual teenage guy, or at least in my early 20s. When I was with my younger brother once, the newsagent refused to sell us a scratch-and-win ticket because we couldn't prove we were over 16 (we were acting very immature).
When I'm walking down the street dressed like a male youth, I notice other girls around the same age group (all over 18, of course, thank you Quod) looking over at me.
It's not that I'm particularly good looking or anything, but I find that a lot of young women dress very sexy and they want to know that males in the area find them attractive. These females look around them to see how the males in the area are responding to them. If they catch me looking at them, sometimes they smile at me. I smile back, and there's a bit of innocent flirting going on.
I really like those little glances that females give males. I think the ones that dress up very sexy like to be reassured that they're looking hot. I love experiencing the male side of this. In the past, when I was younger and went on a road trip with my brother, girls would come up and flirt with us, mistaking us for two guys. As long as I kept my mouth shut and let my brother do the talking, it was all harmless fun.
Most females are repulsed by the idea of a lesbian encounter, so this gives me a chance to feel what it feels like for females to flirt with you.
I hope that sounded less weird. Probably not