Since control group can only be aware of another control group, there are four possibilities for control groups:
Gay girls control group(hot)
Gay Guys control group(Hot for some, not me, except for rule 643y(ghey)of the internet)
Straight Guys control group
Straight Girls control group
So of these possibilities she belongs to two, gay girls only, straight girls only.
In essence, this test would require around 4!/(4-1)! groups, so in other words, it would be the 24/6, or four possibilities of groups she could ACTUALLY belong too(assume SRS), in which she can be gay, bi, striaght, or straight (include herms as straight or bi, either or, doesn't change the experiment). So she has a fifty percent chance of being straight, a 25% chance of being gay, and a 25% chance of being bi. So in this, we must also assume she has a 150% chance of being a hermaphrodite(50%+25%+25%+50%). And.... And....
CONGRATULATIONS!!!! You are dating a lesbian!!!!!! NO MATTER HOW YOU LOOK AT IT!!!... Or you are BHG(take your pick, see otehr post here: http://forums.xkcd.com/viewtopic.php?f=7&t=30682&start=120
Congratulations, the mobius strip that is the internets strikes again!
I think, without a doubt, I have proven that XKCD is a ghey tranvestite that isalso straight, but a hermaphrodite. Congratulations internets, your mobiusstrip strikes again.