I like girly girls, but I like boyish ones too! They're female as long as they identify themselves as such, in my opinion.
On another note, the interactions between them are really interesting. Kisaragi is confident that she can develop a relationship with the tomboyish girl (does she have a name?), but the tomboyish girl just wants to stay aloof and not get affected by anybody. The needling feels less like teasing and more like a struggle for dominance/assertion of personality on both sides, which I don't remember seeing in other romance works. It's nice that it's still getting scanlated/has finished being scanlated.
...By the way, does anybody else think that Kisaragi looks a bit like Irisviel from Fate/Zero or is it just me?