Psychoprotective (Youjo Senki/Psychonauts)

Youjo Senki/Psychonauts crossover.  If you had told Tanya she would enter the military before the notice of conscription came in, she would have laughed at you. It was a recipe for dying young. Now, in her third life, she can try to at least pretend to be an intelligent child rather than rushing for enough status to not be put on the front lines of a war. Of course, this is far from an easy thing, given that it's the Cold War, and they're surrounded by literal mind readers who specialize in espionage. But they can do nothing but try their best. This story is now Complete.