I want to say a few things. I am no game dev, but I think that I have helpful advice.
First off, the goods.
1. The art is good, I dont have to say that though, mainly because the art is on display here, but all the scenerios look good. Characters look distinct and can be recognized both in the overworld and in their more detailed profiles. No one important feels too similar to another character.
2. Changing Story Pathing. I like this idea, and it can be a difficult feature to add in. The fact that your actions can change the narrative is intresting and encourages replays.
Now, the bads.
1. The overworld. It's empty. You can vist the town, meadow, and the acadamy, but outside of that there is no where else to go. I understand that this is a demo, and that there will be more areas to explore in the finished game. But that isnt a reason the player can't visit the other landmarks on the world map.
Additionally, there are no monsters to fight, with the exception of the slime boss and the meanflowers. I'm going into depth with this further at point 3.
Furthering the issue with emptiness, the towns don't have much to do in them either. You can visit the hot springs, but that is only a flag for diverging paths later. The blacksmith dosent actually do anything except for making your weapon stronger.
This leads into the second point.
2. Narrow. The game is restrictive, if the game does not want you to go somewhere until later, the story puts up a very shoddy "No Trespassing" sign in your path, even though you can go there.
For example, the blacksmith. You go to the blacksmith to make your daggers stronger to defeat the big meanflower. It's just a band-aid to make you spend more time on a quest.
I can offer a solution to this though, checkmarks/flags. When the player meets certain conditions, a "flag" or checkmark is read. Changing a "False" to "True", causing the area to change, similar to what happened with the night sequence. For example; instead of having no access to the flower meadow at first, let players go into the meadow but there are no meanflowers, and the monster that stole Era's bikini isn't there either.
3. Combat. In a descriptive term, it's flacid. There is no nuance or strategy involved. You just keep hitting attack until thing is dead (I'm not trying to be mean, but that is LITERALLY the only option, you can defend, but without healing items or skills at all there is no point. There aren't even skills to use, just normal fight.). Hooray, I spent 30 seconds on an uninvolved fight. There isn't even a character progression system. No EXP, no gold, fights just end. Worse still is that these fights are mandatory. Not even random. You have to fight these enemies to progress through the game, but with no other incentive to fight them, I don't really want to. It just makes me want to do something else.
4. Items, or rather, the lack of them. You have an entire gear and loadout menu that you cannot use. You can look at it, see the stats your gear changes, but there is no point to it because you cant change your gear. This is most likely a dev issue, where items and gear are planned, but aren't in the game yet.
5. Story Pathing. I know I listed this as a positive, but there are issues with it as it is implemented. The changes are hardily noticable, mostly boiling down to: Era has sex, Era does not have sex. Now, this is probably going to change further down the line in development, as more options and bridges are made, the changes might become more involved and noticable.
And that is everything I want to say. I know I am probably asking for to much, and that the game is aiming just to be another hentai game, but that doesn't mean that the game should be like this. There are tons of hentai games on steam that have much more going for them than just sexy scenarios and good art.