[3] In the main story, the game takes place in another world and focuses on Levaetein (later revealed as Amane in Zero's Rebellion), a mysterious girl known as a "Killer Princess".

Levaetein now must regain her memories for her true purpose while being joined by other Killer Princesses to defeat the demons plaguing the land.

The story focuses on Zero,[4] the first Killer Prince as he tries to resolve things in the human world, regarding the attack of the demons and the Weapons used to defeat them.

[10] The game had a cross-over event with Brave Frontier and Dempagumi.inc in June 2016,[11] and Puella Magi Madoka Magica in November 2019.

This might be common practice in the games that inspired it, but when you’re already struggling to keep players engaged because of frequent loading and needless menu navigation, adding even more into the mix slows the experience to a crawl.

"[13] Siliconera described the game as a "well-executed copycat" of Fire Emblem, that made up for the lack of character development with making it enjoyable to build fighting teams based more on skill and appearance than relevance to the story.