SubaHibi takes the all-time record for utterly and completely betraying my expectations. But in a good way.
While I can't say exactly how, since it's all spoilers, suffice it to say there are more red herrings than you would dare suspect, and all the real answers are seamlessly hidden where you would never think to look (or do, but can't discern any meaning from). By the end of the game, the sheer volume of things you thought you knew but didn't created something rare for me: an irresistible urge to replay earlier chapters.
At the very beginning, the characters feel almost trite, but once things get going everyone is complex and engaging, and of course a little incomprehensible until near the end of the game. They also succeed at making most of the slice-of-life scenes between plot points entertaining, either comically or intellectually. A few of them are hard to call believable or human, but that's mostly because plot screwed them over. Also, even those trope links stop applying to those characters once you know the truth.
Unfortunately, this game is in serious need of pruning. The infamous bullying scenes in particular should be half their current length if not shorter, and there seems to be a constant supply of dialogues which are interesting but just long-winded enough to get annoying. There are also several times when you're forced to rewatch a scene from another character's perspective, and either nothing new is added or it was already quite obvious to me what would be different. Finally, one part of the game got no explanation at all despite very thorough explanations for everything else.
Good news is, all of the truly severe cases of bloat are easy enough to identify that you can just ctrl them without hesitation and get back to the good stuff. In the end most of the above was more of a huge nuisance than a fatal flaw, and the story was never in danger of completely losing its momentum or intrigue.
Depends how irritated you get when a game switches back and forth between epic cliffhanging twists and slightly-too-long comedy/slice-of-life filler. It's also likely some people will be more liberal with ctrl than I was or fail to figure out quite as much in advance, making them immune to some of the aforementioned problems.
Routes/Endings Played: All Endings.
P.S.: There is almost no philosophy whatsoever in the entirety of the story, and the book quotes are sparse after the prologue, acting primarily as something for characters to talk about once in a long while between more important subplots. You need not understand nor have read any of the books SubaHibi references in order to understand the entirety of SubaHibi.