Scarlet by A.C. Gaughin

Will Scarlet is a well known thief, a part of the much loved and vilified troop of thieves led by Robin of Locksley. As Will, Little John, Much, and Robin steal from the rich to give to the poor, Will Scarlet must also deal with the ongoing secrets that he lives with: he is actually a she and she has a past that is catching up to her like the hangman's noose. As she deals with a confrontation with thief catcher Guy of Gisbourne, she must also pick through the conflicting emotions she has for Robin and the attentions of Little John.

HOLY BANANAS THIS WAS AWESOME! AWESOME I SAY!

Scarlet was such an incredible, deep, layered character. She was thoughtful strong, and best of all realistic. She was not a wilting flower pretending to be a boy, Scarlet was fully committed to her ruse and was rather disgusted by the idea of skirts and flirtation. That's not to say that she isn't sympathetic to the female plight. She has a back story that unfolds beautifully and naturally, kind of like her feelings for Robin and her confusion about Little John.

SPOILERS HINTED AT AHEAD