"Why, of all people, would someone like me need a future diary?"
You, a sassy "little" trickster with an affluence of dark thoughts, have been selected as the hidden thirteenth member of the game, completely separate from everyone else as to challenge the remaining members in the final weeks; For once, Deus Ex Machina wasn't acting like a Deus Ex Machina, in fact, the opposite.
Originally supposed to appear in the endgame, you grew tired and decide to meet with the others.
Seeker of revenge and answers, you have never, ever imagined leaving the Military Police to join the Survey Corps. The Commander Erwin Smith seems to have an eye on you since your first encounter, and so do you.
Everything you've done, you've done it in order to find answers to your enigmas. However, as time passes after your entry into the Scouts, what if in someone else's eyes, the actual enigma happens to be you?