Hello there! Welcome to Feedback Quest RPGs! My name's Hythrain, and I'm one of the streamer's for Feedback Quest and also a host for mini events like this. I'm writing this feedback after having played your game live. If you'd like a link to the VOD when it's posted, just let me know.
So right up front, this is a very RPG Maker game. It looks the most RPG Maker I've seen, it sounds the most RPG Maker I've seen, and its combat is the most RPG Maker I've seen. That is to say, it's insanely hard from the beginning with lots of misses and enemies having tons of health and such, where you could end the very first random encounter with your team half dead and one poisoned if you're not paying attention to how you're using your attacks rather than towards the end of the game. I went to the gameplay and immediately had no idea where I was to be going. After the first fight, I did indeed have a character poisoned and was trying to get gil to buy something to get rid of it. However, the only available town was way up north and I didn't even have half the gil I needed.
And this is before getting into a problem with making everything dark based if the dark-only character can't heal (Makes that person useless while pushing double duty onto the light-only character).
However, these are ultimately issues of RPG Maker itself. If a game was being programmed from the ground up, these are all things that would be made to operate differently. As such, what that leaves is that this title needs to be judged on its story. This, however, proved to be more difficult than I expected.
First I had difficulty figuring out what to do. The player starts with several options on where to go, even when only going gameplay, and the sheer difficult can make it difficult for the player to want to wander far from the only available town let alone take on a dungeon. However, once I got over this and got into the tower, I began moving forward. I had these two characters, who are essentially representations of angels and demons except reversed on the good/evil side of things; Argenti, the light angel who is basically a paladin with higher attack and defensive and Aegrit, the almost god-like priestess of darkness who for some reason refers to Argenti as "Prisoner." It makes me think that in this world, even evil or gross behaviors are seen as good and vice-versa. Then I learned this wasn't the case, that things of depravity are seen as things of Light thanks to erotic faeries. So instead, it turns out Aegrit is just an asshole.
This leads into the my eventual progression into the tower and meeting Cielle and the smashing of two things. When Cielle wants the shards, I ultimately had no items to give her despite collecting them. So not knowing what I was missing, I moved onto the next part, got to the town and then saw stuff I don't know if I'll ever unsee. Anyway, this leads into the final dungeon where I honestly didn't understand the clue being given for what to do. Then after a few teleports, I ended up on the walls and was in a panic trying to get down. Finally, I got to the boss and fought it, with things ending with them getting a seal that needed to escape wherever they are to get to wherever they're going.
If you noticed how I seemed to not understand certain parts, it's because your demo is set further into the story without any sort of proper introduction. I then remembered that at the start of the game was an NPC who said something about story. So I went back to it to read that story, thinking maybe you're making this story as episodic and perhaps there were three other games.
Nope, the bulk of the story was done in one dialogue box. The goal was given in the second. No answers were to be had for me.
So while this is a demo, not starting at the very start of the story hinders my ability to offer any proper feedback. RPG Maker things are just that: RPG Maker things. With that said, if you have other parts already made and you're only showing this later part, don't do that. Just let the player start at the beginning so they can judge things better. Either that or throw away RPG Maker and build your own combat system that would be suited to your story instead of using a generic and very punishing combat system, because otherwise you're not giving people anything to truly latch onto.