Amnesiac from the Start, Then the Perfect Undercover Agent

An SAT intern injured on the job is diagnosed with dissociative amnesia. Now there's a self-aware "book" in her mind that only she can see. Aside from making her already severe dissociative disorder even worse, the book's main purpose is to give her a place to vent and make snarky comments.

Already on the verge of being medically retired during her internship, she has to become a tireless workaholic and put in overtime to keep her secure job, proving to her superiors that a little amnesia won't stop her from being the Tokyo Metropolitan Police Department's best sniper.

But there's one small problem: the book tells her she's also the Organization's Rosé.

And another little problem: she seems to be an undercover agent for Public Security who has lost contact with her handlers.

And one last tiny problem: why do people from Yokohama keep coming to Tokyo to make themselves known?

She can't help but feel a deep respect for her pre-amnesia self. I must have been an Oscar-winning actress before I lost my memory to pull off this many layers of secret identities.

Content warnings:

1. This story has a lot of potentially triggering elements. If you need to check warnings before reading, please don't click in.

2. Romance is not a major focus. The male lead has not been decided and will depend on how the plot develops.

3. The main series is Detective Conan, with Bungou Stray Dogs and Detective Conan merged. The worldbuilding includes an extreme amount of headcanon.

4. An extreme amount of Conan-style science, an extreme amount of out-of-character behavior. Any headcanon will be explained in the author's notes.

Theme: "Who am I? Where did I come from? Where am I going?"