Senjou no Princess ~The Princess on Battlefield~

Senjou no Princess ~The Princess on Battlefield~ (戦場のプリンセス ~The princess on battlefield~) was a game planned for the Continent series, but was never released.

Images and sketches of the game can be found here: https://web.archive.org/web/20041018213850fw_/http://quinrose.main.jp/gallery/ira.htm

Some fans also had a discussion about it here that is informative: https://twitter.com/i/moments/1033518633241075712

Plot
"アラビアンズ・ロスト等と世界観は同じですが、戦時中で、時代もコンセプトも異なります. 切ない系恋愛で、色んな意味で大人向けです. （全年齢対象ですが・・・)"