I don't play Visual Novels usually, so please keep that in mind.
Transition between Main Menu, Preferences etc. is a bit slow. UI Looks a bit Sci-Fi-y, is that intended for a Catholic School?
AI Graphics in a Visual Novel, really?
Some of the Information seems overly detailed. Why does it matter that the Door is a double metal one? You also have an entire Screen worth of Space to use, why is there nothing for the Intro? But the Intro shouldn't be like that anyway I think, better to start off in the School and use Conversations with the other Students to talk about what happend and/or how you got there in more Detail.
The Bible Quote Part seems oddly placed and kind of shoehorned in. Kind of like you have 2 different Intros now. Would maybe be also better as in School, maybe as a history class or something?
Saving works at least, nice that RMB also lets you move back.
You're AI generated background Images don't fit the Text description. Expected.
I understand that its a Christianity-based Novel, but it reads more like Advertisement half of the Time.
Is Father John supposed to be a Minotaur? Not all that attractive, I think its the Ears. Or maybe the Facial Expression. Or the Hairstyle clashing a bit with the Horns. Which also seem to extrude out of the Hair not the Skull. The Hair should flow around them a bit I think. Damien is way better. Thought he's a Vampire, but apparently he's a Daywalker. Fine with me, but shouldn't he keep a more humanoid look then? Less pointy Ears, more natural Skincolor, maybe no red pupils?
I like the School Uniform, but the Pattern on the Pants/Tie is just lazily pasted, and doesn't follow the flow of the Cloth.
Do you need that long a description for the Harpy? You have the Images after all.
You even have the "I cut the Intro short here" Part in talking to Sera, you could just put the Intro in there, or later on in an explanation to her.
Slime description, again you have the Image for most of that. Whats with the Antenna talk? Is it a Snail now or something?
The Cathedral background looks especially unfitting, its inside a Town, not a School, and the Brikwoork doesn't work well at that resolution. Also its a School, why does it have an entire Cathedral? A small church or Shrine should be more then enough.
Apart from sounding like Advertisement it also seems like its a bit of self-ego stroking, with all the talk about how Christians are basically better then non-christians.
Wish I could name Saves, so I can easier remember what Point in the Story they are for.
Backgrounds change from daylight to nightlight as they see fit, not as it should be for the Story.
Didn't know Gabriel was supposed to be buffed in this. But I guess since he's one of the good Christians, constantly talking about his Love to God, and his Bible placement, He needs to be. And of course meditating by praying in the Shower. The Intro talks about him being more of a "Go to Church and thats it" kind of Guy, but one Day into the School and he talks and acts more like a young Priest? Something feels off here.
Despite being a life-in School, theres no breakfast? But Dinner was mentioned before, so there definetly has to be a cantine, right?
Harpy in the Basketball Team? Sounds like cheating, if she can fly/hover. Isn't cheating un-christian?
Sheep-Nun-Teacher. Thats fitting. Gabriel having to introduce himself awkwardly made me wince. Didn't want to go through Stuff like that, but I guess it had to be.
Of course Class begins with more Advertising. Also noticed that only the Girls are introduced at all, I'm assuming its because they are the only dating options, and this is ment to be a dating Game. Makes Sense since there is no Player customization, but it feels a bit unnatural. Maybe introduce one or two Side characters aswell, you can use to get some special Items or Information, some Help or whatever in the Endeavor of romancing whoever? You have Damien ofcourse, but thats a 1 to 5 ratio. I'm not counting the Minotaur, he's neither cute, nor would he ever help with something like that I assume.
Of course Gabriel is also a quick reader, smart, buff, probably handsome, a Knight in shining Armor, good with People, good at Sports, etc. Is there anything the main Character is bad at? Any kind of Flaws?
"All this religious theology right off the bat on the first day is a lot to take in." - Yes it is. "I believe it all of course" - Of course you do Gabriel. You're a perfect Christian after all. And of course if basic religion and philosophy were tought in all public schools, it would encourage more thoughtful discourse. We had Religion in School, as a mandatory class, either Catholic, Protestanthism, or Ethic if you're not comfortable with Christianity due to being Jewish or something. Pretty much everyone just slept through it, nothing remained, nobody bettered themselves through it, it was a waste of Time. Not the Teachers fault, he was a really nice Guy, friendly, trying to help and so on, as opposed to some of the Others, but its not something that any of the Students would be interested in at all.
Class goes for the entire first half of the Day just asking Students about how Christian they are? Now thats a waste of educational Time.
Finally Time to choose a Route. Its an obvious choice, I can't identify with the main Character, so I'll just swap things around.
Now things get troublesome, Anime and self-improvement, aren really hobbies I think. I can see Anime being a discussion here, but self-improvement should be in anything, not something you dedicatedly do in your free-Time. Gaming and Reading are the obvious choices, but as a perfect Christian, Gabriel probably thinks of self-improvement as his Hobby, right? Lets go with Reading, see how obvious the Route goes. Of Course Gabriel reads a lot on Religion and the lives of different Saints. Is his Life just completely devoted to anything religion-like?
First he has to say he's reassuring Eva, then you have the reassurance itself be displayed again? Do you need double Dialogue like that? And of course the Reassurance is half insulting by telling her that she constantly has a book in her Hand. She's supposed to be shy right? Would never invite you to the Library and/or try to help you find a book by herself. Not a Chance. If anything Clover should tell Gabriel that.
I said Gabriel likes reading as a hobby, immediately after that Scene he thinks about how he constantly talked to his Friends about Shows or Games tho, so I guess I was lying when I assumed his Hobbies? Not very Christian of me, Sorry.
Gym Background are some Trees, but Sounds are balls bouncing on Gymfloor. With a lot more talking then there should be. Also seems to be Gym is more of a relaxation period here with everyone doing what they want, and half of them just not doing any Sports at all. Is that how it is in America? Either Way, continuing trying to cheese through a route in the most obvious Way. Also Gym is Boys and Girls combined? Never, I refuse to believe that, especially in a catholic School.
Of course the first Way to redirect the talk away from Games is religion. Let's try it, I'm a bit curious on their opinions anyway. Not like I can't just save and reload, thank you for that, and thank you that its actually working. Of course Gabriel is just a raised Catholic, nothing special. Everyone of those prays in their morning Shower, works out every morning, is friendly, open, smart, and basically perfect in every Way. So more Advertisement. But this Time its on me, I chose that option myself after all.
At least its giving me pluspoints it seems, so good Choice.
Seeing as Gabriel is the perfect Guy, obviously he's beating the Basketball-Teams Harpies Score first Try. How else would it be?
Library has pretty much only Christian Books in it it seems. Works for a Catholic School I guess, but seems a bit slathered ontop of everything else. Would it hurt that much to have a bit of not-overly-Religious Stuff in there? Doesn't have to be straight up anti-religion or questioning any beliefs or whatever, but just some normal Stuff that doesn't stray into any Opinion? And of course even if I pick the least Religious book, Gabriel just immediately makes a Jesus reference over it, and how good it is for Religion. He's pretty much a Saint after all.
Can't pick a Romance Novel I guess. Rude. Guess I'll just read everything else then. Seems to not do anything, as long as I make sure not to pick Romance. Don't care much about Monster Girls, asked about Succubi just in case it matters.
And again, Gabriel spends his free Time Gaming. I really lied when talking about Reading as a Hobby, didn't I? Almost has me wanting to load the old save and redo it all. But that'd probably go against the chosen Route. And of course Gabriel has to repeat how active and great he is every morning. But only ever eats Snackbars for Breakfast? Either eat a proper one in the Cantine or none at all, not Snacks first Thing int he morning.
Monster mash Halloween Dance in a Monster School. Heh, nice. You better have interesting Costume Sprites tho, if they just dress as themselves thats immensly boring.
I get a choice for a lot of Stuff, but not to choose Music or Art? I have to go with Music? And the Music Room uses the same Background as the regular Classroom? And first Thing during Gabriels talk with Aria he does is lie about the Battle of the Bands. I guess he's not that great of a Christian after all, constantly lying to get on the good Side of People? I personally hated singing, and singing in Choirs or Groups very much aswell, so none of that Soul Harmonizing Stuff, but I also dropped Music Class the first Opportunity I got, so I can't relate there. I can't related with pretty much most of this anyway.
Aria as the Musical Bandmember just mashes Rock, Punk, Emo and Goth into the same darker vibe evil music Genre? Doubtful. But sure, its Devil's music after all. Reloaded to just go to the Dorms immediately. Don't want to accidentally go down a wrong Route or something. Was only hoping to maybe run into Eva anyway, not into Aria.
Of course reading immediately starts with Advertising Christianities greatness or something. I don't know, as soon as something like that comes up I automatically turn off and skip through it at this Point. Of course Gabriel also exclaims he's not really all that Catholic or whatever when asked about it in the Cathedral. I sure hope Father John is not giving a full on Lecture at this Point. I expect it tho.
Surprising end of the Demo, alright, I've played this long enough anyway.
Unsurprisingly would've gone down Evas Route. But what about Aria not liking dances? As a Band-member/Music inclined Person?
Overall a lot of the Text seems redundant, backgrounds need work but you said they are mostly AI generated at this Point if I recall correctly. Eva has a few Parts where she's really not acting like a shy booknerd would, Gabriel feels like he's too full of himself and constantly praising how great he is throughout the entire Novel, either by himself or through the Author, and most of this reads more like Advertisement for Christianity then a Visual Novel. If anything turned me more away from it then to it tho, probably not what you intended.
Please keep in mind, I don't play Visual Novels, I can't connect with Gabriel, I'm not overly Religious ( I'm not against it or trying to hate on it either, but just so you know), and this is pretty much in absolutely no Way intended for me.