My impressions, I'll concentrate on the bad since there's not much of it and correcting these issues would really catapult your project to a high level of quality and bring out its true potential for success. Please understand that my overall opinion of your game is quite positive and you've done far more right than wrong, so please take this as constructive criticism.
- It seems obvious English is not your first language, as you have a strong grasp of plotting, worldbuilding, and characterization but your dialogue and other text is frequently clunky at best. Your characters all seem to speak in similar ways using similar choices of words and idioms and such, when they should have their own style of speech that is as distinct as they are. The sex scene dialogue is particularly rough and there's way too much repetition of ohs and ahs and cringey porn lines and "awwn" which is something I've never heard in English yet all your characters use it. It would be good to cut a lot of the excess sex scene dialogue and replace it with narrative description, less is more when it comes to that sort of thing. As an erotic fanfiction writer myself, I know that sex scenes are among the hardest thing to get right and the text portion of your sex scenes are honestly your greatest weakness as a writer that I've seen. If you do nothing else, rework the sex dialogue and trim it down and you'll vastly improve your game.
Honestly, I would suggest if possible to get someone who's a good writer with a native grasp of English to polish your text as it's really the one thing holding this back from being seriously great.
- You have clearly done very extensive worldbuilding in the setting and have quite the cast to explore and showcase and that is a very good thing. I personally am a sucker for good worldbuilding and a good cast and you've got that going in spades. However, you also have a lot of information and content packed into a rather short overall runtime and it's going to be overwhelming for a lot of players. I mean you have an entire cosmology and set of world metaphysics to bring us up to speed on, three worlds (hell, the human world, and heaven) to lay out for us, and a wide cast of characters and significant power players with roles to play in the plot. The material is quite good, but there's a lot to memorize in a relatively short time and a lot of people are going to find it tough.
First thing I would suggest is trim your cast somewhat, or at least save some for later chapters. For example there are a ton of villagers in the first area that seem to be there simply to provide a sex scene and little bit of fluff interaction and play no further role in the story. I can't remember most of their names or most of what their particular defining characteristics were and primarily the important minor roles seem to be the teacher, the innkeeper, the mother daughter pair who serve as a connection to the second chapter, and the woman who vows vengeance on Bartho thinking he killed her son and the little girl. There were just too many names and sets of details to memorize and I lost track of who is who pretty quickly. I say if you're not going to cut some of them out, mark them as optional side characters there for sex fluff so we know to not try and memorize them instead of keeping our primary focus on the characters who matter.
Similarly, there are a lot of demons and such and some of them at least seem superfluous. Again it's a lot to memorize and keep track of, and I don't recall all of them for the same reason I don't remember all the villagers --there are too many of them who don't get enough screen time to make an impression. There's the girlfriend, the sister, the ex girlfriend, and the antagonist who play a major role, but there's also for example Melty and a red demoness who both have the same goal of seducing Bartho in order to learn something from him and unless they both become important later for different reasons they should be merged. Or, since the red demoness really doesn't do much in the content we've seen you could save her introduction for later when she becomes important to the story.
None of these are bad characters, mind you, but when it comes to introducing a large cast it's important to take it slow and introduce them a few at a time or perhaps an initial batch and then one or two additional characters at a time to expand slowly once the player has had time to absorb the initial ones. Think of it like building a house, lay the foundation and solidify it before adding on the rest of it at a manageable pace.
Another thing that would be helpful is to add a codex in the menu or something that has basic information about characters, locations, the major events that have taken place thus far, etc that the player can refer to whenever they're trying to recall something or they want to review what they're supposed to know in order to solidify their grasp. These entries should be concise and just cover the important need-to-know facts, more brief summaries than comprehensive knowledge. The more detailed stuff can go in the fan wiki!
Beyond those issues, which are relatively minor and the kind of thing that typically gets tightened up and polished in later drafts and an editing process, there is very little not to like in what you've presented. The setting is intriguing and well constructed, the characters are compelling, the visual designs are enticing, and the plot is complex and well constructed. The main villainess in particular has the "love to hate" quality a good antagonist thrives on and you've done an excellent job of making her origins sympathetic and her reasons understandable while her actions based on them have been unforgivable. That's a tough balance to strike, and such a villain when done right as you have is storytelling gold.
I'm definitely looking forward to more of this story, and I hope my advice from one writer to another can be helpful in getting your work to the next level of excellence it has all the potential to achieve.
