War Maidens and Warfare 6: Valkyrie Edition - 戦乙女といくさごと! 〜戦乙女編〜

This is the last of the War Maidens and Warfare series. From what I heard from someone who heard someone, apparently the author is currently working on another doujin series alongside their non-hentai manga series, but the manga takes priority so there is no telling when the doujin would release. Note that each editions of this series took nearly a year to make and this one is only a few months old. So we'll likely not get a continuation in the near future.