Author's Name: Dang. Shortest thing I've written in a while. Not even 1000 words long, but it decided on its own that it didn't want to be longer, so I left it.
Disclaimer: Gosho Aoyama-sama owns Detective Conan and I'm merely playing around with one of my headcanons.
Vermouth's Secret
Most people in the Organization remembered a time before the Organization reached out to them. The Organization had reached out to them and they accepted the Devil's hand. That had never been the case for Vermouth. There was never a time, not even as a child, that the Organization had not played a role in her life, for she, like the Miyano children a generation later, had been born into it.
Her mother had always been glad that she took after her American father instead of her Japanese mother. "Nobody will ever guess that you're mine, my little grapevine," she had said with a contented smile on her face as she ran her fingers through her fair blond hair.
That had not been enough for her mother though because she was a very important person in the Organization. Despite her father being dead before she was born, Sharon had been gifted her father's surname, Vineyard. Even in elementary school, she was already learning to disguise herself as someone else and she learned the art of secrecy at her mother's knee. She was not allowed in her mother's presence in public and if anyone called on her mother in the privacy of their home, then she had strict orders to hide and keep quiet. Very few people even knew of her existence. Her mother's friend named Pisco was one of her most frequent caretakers. Sharon Vineyard grew up in a world of secrets, lies, and deceptions, her mother both the God and the Devil of her domain. That didn't change when her mother decided she was old enough at thirteen to be put to work for the Organization she been born into. She was granted the codename Vermouth, her mother's favorite wine, and the newly-christened Vermouth was no longer allowed to call her 'Mama' or by name, not even in private. Instead, her mother had a new name for her to call her: Boss.
I have so many different headcanons about different things with the Black Organization and many of them contradict each other, so I'm not too sold on any single one. This particular headcanon stems from my desire for EITHER Rum or the Boss to be a woman. I believe that they're not the same sex and I want one of them to be a woman. The idea of the Boss being a woman is particularly attractive to me, however, because of the kind of personality that Vermouth is, I can't imagine her being known as the 'favorite' of any woman unless that woman is her mother. That would fit with what little we know of Vermouth too. It could explain her particular hatred for Sherry if they shared a similar origin of both being born in the Organization. Being born in the Organization would certainly be reason enough for her to claim "I wonder if there really is a god" and "No angel has ever smiled upon me". If this is the secret Bourbon knows about her relationship with the Boss, it would not be something Vermouth would want to get out to other Organization members and it would definitely be surprising to them. Vineyards are where grapes are grown for wine, so there's a potential intentional connection there. Even the text the boss sent her after her confrontation with Jodie, Conan, Akai, Haibara, and Ran could be read as a mother scolding her daughter.