@UnknownSaint111 Was that sarcasm? Nobody has ever been satisfied with an open ending. In this case, it'd even be a step backwards since there's already a couple in the series.
I have gotta hard agree with @Glomoro on this one. Open endings are never a good option. Likely scenario is it goes for only girl, Yukana most likely, and leaves you feeling slighted like any visual novel ending would. Best case you get an actual well-written harem ending, but that's asking for too much from the author at this point