From playing the demo: they just took the code and assets from their last game, added some music, backgrounds and tentacle monster animations and then slapped it up on dlsite.
I can't really blame them, their last game sold poorly so they must of needed to make some money quick to stay afloat. Tentacles sell better than weird humanoid things according to how well their previous action games did. Or maybe it was just because of how basic game play wise the last game was that made it sell so poorly.
Personally I'd love to see them make more of the BFRPG games they did with the fullscreen animations, the 2 that they made were great.