Battle card game by Lilith which is happening in the Taimaninverse, but outside the main canon timeline of the Visual Novels, where the heir of the Fuuma clan wants to weight into the balance between the three forces (Taimanin, US and Demons) after the collapse of his tribe.

It is a massive crossover with characters from multiple games where most stories are hypothetical "what if" scenarios.
Taimanin Asagi Battle Arena takes place instead of the events of Taimanin Asagi 3, in an alternative timeline.