So, that was a trip...
Overall, despite the grammar in Act 3 becoming more hastily done Zero & Cecelia's names got swapped like twice in narration dialogue, this was very nice.
I definitely found the irony in CC's identity --of which I won't spoil for those reading-- amusing, I honestly want to check out your other projects to just get more context, especially if the NULL and the WAR are subjects that have been alluded to before.
Otherwise Fouzi, you have truly made something special, this shit could fucking be a standalone manga, with of course the twist being that every book on the surface is completely unconnected, but after reading, they combine into a cohesive narrative.
You are indeed on my radar, and I don't regret sacrificing 2 hours of my life to your product.
TL;DR: Game good, makes you think, good twist, definitely works better with context from the previous games... presumably.