Continuities

The events of Assault Lilys story exist in different continuities' depending on the medium. Some of these events contradict each other between continuities.

Novels
The oldest continuity is that of the first two novels, Assault Lily: Move Out, Team Hitotsuyanagi! and Assault Lily ARMS. These novels feature differences in how Team Hitotsuyanagi came together and also the fate of certain other characters.

Stage plays
The stage plays have their own continuity. Most notably, Assault Lily: League of Gardens tells a very different and irreconcilable story about Team Hitotsuyanagi's formation, and the early relationship between Hitotsuyanagi Riri and Shirai Yuyu, from the story that Assault Lily: Bouquet tells.

Anime/game
Assault Lily: Bouquet and Assault Lily: Last Bullet both take place in this continuity (Last Bullet contains a fairly faithful visual novel-style adaptation of Bouquet as an in-game "legion story" for Team Hitotsuyanagi.)

As of chapter 2 of Last Bullet's main story, the line between the anime/game and stage play continuities has become blurry. This part of the game story seems to be written as if most events from the stage plays, such as the battle in Shimokitazawa and the disasters at Ludvico, took place in its continuity. It's not clear at present how these events are meant to fit together.