The climatic scene of the quintessential 80s teen comedy "Just One of the Guys" plays out as follows:
It's the prom (of course, it's the prom!). Best friends Terry and Rick attend, the latter hopelessly dateless. But Terry won't have that: he proclaims his love for Rick, kissing him on the mouth. Oh, 80s teen comedies!
Then, Terry opens his shirt, revealing two giant... breasts.
Of course, that's not exactly a surprise to the viewer: they've been following Terry for the duration of the movie, and know that he is really a she. Terry actually attends a different high school, and is trying to prove to her journalism teacher that a woman can be a serious writer. So she goes undercover as a man... stop us when this starts making sense.
Now, what comes next is the most insane part. Rick obviously rejects Terry, but comes around and begins dating him... her. Think about it: here you are, hanging out with your best friend for a year, find out he is a she, and then shtup him... her.
Oh, 80s teen comedies!