The plot: interesting, the setup: confusing. I gave it a four because "decent" sounds better than "mediocre."

I'm not quite sure what to think of this manga. It has quite a bit of potential, but it's story is too short and cluttered to tell what's really going on in it. Throughout the story, there seems to be a few flashbacks explaining things. These aren't well organized and they just confused me even more.

Since it's based on a game, I can assume only the people that have played the game really have an idea of what's happening. If you haven't, it's likely that you'll be somewhat confused.

I've also looked it up and it seems that it's soon to be an anime. I'll look forward to watching this and hope for the best.

To sum it up, I'd say not to get involved in it if you're only wanting to read the manga. But, if you've played the game or are interested in watching the anime, I think it's worth a shot.