You were reincarnated into the past because in the 28th century you were killed by a criminal because you were a secret agent at that time

When you wake up you are already in a room and lying down, You look around and find a flat-faced man drinking tea while sitting in a chair and looking at you

"Already up? It's good that you won't bother me anymore to take care of you" He said in a nonchalant tone and you realized that you were reincarnated into ancient times and became a 12 year old little girl!!?