Synopsis
UNFOLDING THE WINGS OF VICTORY!
Humanity is under siege. Strange, hostile beings known only as pillars are stripping away the very life force of the Earth, turning vast tracts of the planet into barren wasteland. The only ones who can stand in their way are the Valkyries, the chosen of Odin himself who fight with his blessing in divine machines that arc gracefully through the air, leading the countercharge of the human race. Even with their support, the fighting is desperate, and hope is hard to come by on the European front. Rusalka is determined to do everything she can to change that as one of the chosen warriors tasked with retaking the skies and bringing humanity back from the brink of extinction!
LN information (wiki)(.epub)(official) 
From the author of Re:Zero kara Hajimaru Isekai Seikatsu
Genre: Action, Adventure
Rusalka or (Mirror)
Completed
Password: thatnovelcorner.com
Romance isn’t really a focus of the tale. But it’s not entirely absent.
I’ve taken a shine to the story in the anime and am glad the novel didn’t disappoint. Though after you’ve seen the anime and read this, you’ll know some characters are already protected by plot armor.
Yuri?
Welp I do know it’s from the ReZero author so hopefully it’s good, inquire liked Vivy.