Unknown to her, Sano figures out she is a girl within the first volume. But he doesn't tell her, so the ruse continues for the next 23 volumes.
Not exactly Twelfth Night in which the clueless Duke Orsino doesn't figure out his attendant's identity as a woman until face-to-face with her twin. But within the same ballpark.
I tackle hidden identities of a similar nature in Richard: The Ethics of Affection.
What's the attraction?
Part of it, of course, is the attraction of the "reveal."
But part of the attraction, I postulate, is the girl-dressed-as-a-boy gets to relate to her male lover as a boy. It must be easier!
The truth, of course, is that all relationships--especially with the addition of sex and long-term commitment--take effort and involve misunderstandings. House presented a singularly bizarre and clever episode in which one member of a lesbian couple wants to leave. But she develops an illness and one of her organs fails. Her companion is the only one who can offer a successful organ replacement, and the ill woman doesn't protest. House is contemptuous of the self-serving attitude of the ill woman. However, it turns out that her companion knows that her lover plans to leave. She intended to give up her organ to keep her girlfriend with her forever. Except, the illness is the result of her gift, a dog with the bubonic plague.
Confused yet? Welcome to relationships.
Still, the perception is that it must be easier for women to relate to women and for men to relate to men, and historically speaking (and biologically speaking), this is to a degree true. Friendships still follow these patterns, despite protests from purveyors of abstract theorizing. (Alienating humans from their animal-mammal selves by forcing abstract opinions back onto the physical self is one of the most unsettling heartaches of the early twenty-first century.)
But it's rather like comparing the way dogs chase cats while cats, in some households, put dogs in their place. Sure, dogs might relate more easily to dogs and cats to cats. They both still understand each other better than the strange humans who feed them.
Solving the individual relationship (this person and that person) is always the burden of romance. And every relationship has its own oddities and problems, just as every relationship in history--despite, again, abstract theorizing and labels--had its oddities and problems. Every person is ultimately a person--a mammal, individual person.
