The identity of Hikaru ShiroganeColonel Hikaru Shirogane is an Original Character in Muv Luv DYRL whose is also Shogun Yuuhi's right hand woman. Not only is she powerful but she also knows Mobius Squadron is not from this world and is a backer of Project Valkyrie. There are several guesses on who she is:
What really happen in Yokohama baseIn this fanfic, Yokohama base is destroyed after most of the members of the A-01 Valkyries are revealed to be members of the Allegiance Cult Terrorist group where they kill one of their members for helping the base personnel escape before blowing themselves up along with Yuuko. However, the story is told from news sources and even the people who knew them find it hard to believe they were Allegiance members and did what they did. Because this plot was not told from their point of view, it suggests what happen in Yokohama was an act by Yuuko and the A-01 Valkyries who faked their deaths for their own reasons.