Yep, that confirmed it. He's crossdressing for the sake of getting girlfriends. And Kitano's right, he's technically decieving them. I believe he wouldn't get so many girls' contacts as a man, and that's reasonable. People of the same gender be friends easier because usually friends of the same sex wouldn't want to have sex with each other on default.
Good news is that they'll be more comfortable, but bad news is that none of them would see you as a potential romantic partner. Because no matter what you say about 'love is love', gender and sex undoubtedly plays an enormous part for most people's romantic relationships.
And despite all that, Girly actually managed to make him feel flustered with his appreciation. Very interesting, how much charisma is in his stats?
And finally, their plans to tackle the girl is actually quite brilliant, albeit a bit pervy, especially since they're letting the only one of the group who looks like a boy to do the peeping.
I wonder what's going to happen next, and more importantly, I would like to know how they're going to explain it if they eventually get busted. But no worries, this one's likely a boy as well, so no gender problems. (still quite curious about how did that person do so well in crossdressing though)