This is absolutely one of the most beautiful visual novel-style games that exist, a lot of beautiful quotes that are not randomly placed but fill the parody world that has been created. All the "extra" characters from other series are also an excellent choice, since Gabriel is already there, could you also put Satania in the future? I can't wait for it to go on.
Edit: right I forgot to mention that although it's an eroge it could just be a non-h game for a wider audience if you want