Finished the demo. Played each door in one sitting, which took... longer than I expected each time.
I like the episodic structure. My visual novel experience (not counting hybrids like 999 or Phoenix Wright) begins and ends at Saya no Uta; everything else I've tried takes so long to get going that I often quit ten minutes in. The House in Fata Morgana doesn't suffer that problem. It delivers the hook right away, which has kept me on board. And even if I'm still far away from discovering the true mystery of the mansion, each two-hour chapter delivers a beginning, middle, and end of its own kind of tragedy, so I don't feel like it's wasting my time.
Visual novels are a weird sort of media. They're a less literal storytelling form than movies but more than books. All the images are approximations, coming up short of the fullness of what the prose might describe (and on occasion contradicting it). I'm never quite sure what to think about them. Why not go all the way, or, in the alternative, get the pictures out of the way of the writing? Why stick with blurry backgrounds and the limited shorthand of a handful of character poses (almost like an old JRPG)? Even here, it's a constant problem, as I sometimes found myself torn between following the changes in the character portraits, or maintaining the pace of the developing story.
As far as I can tell, there are a few reasons. The first (which both Saya no Uta and 999 use to some degree) is the way a visual novel can create this ambiguous second-person narrative space. The fixed perspective and constant need for input force a sense of participation in the story, without removing an author's absolute control over the narrative space. The second is the power you get from marrying audio and text, which plays on the reader's imagination in a unique way. The third is the power you get when you bend the otherwise-rigid rules of how a VN is delivered, which can deliver something uniquely impactful to the reader.
What I'm trying to say is that I'm pretty impressed so far. I've got some quibbles about the prose sometimes (particularly how Door 1's occasionally-colloquial dialogue poorly matches the setting), and it's certainly... not exactly subtle when it wants to deliver an emotional punch. But so far, it earned my investment. The art is strong, the music varied, haunting, and evocative, the writing generally has a good grasp on tone, on tension and release, pacing the drama of each of these little tragedies so that they have the appropriate impact. And while I'm not sure how much I approve of some of the more blatant visual novel tricks it pulls to keep me in the dark (blatantly censoring information in front of my eyes on a few occasions), it's still doing a good job teasing out the mystery it delivers up front. I have a lot of questions, a few theories, and very little sense of how the larger tale will play out.
Even if I don't get a free copy, I might still buy the game before the sale ends. There's still so much more I want to know, I don't know if I'd feel comfortable putting the whole thing aside and leaving it.