First thing I want to say is this game is very difficult. Very difficult. In some ways this is good; I love hard games. But this game is also the other kind of difficult, which leads to frustration. So let me tell you what I think of this game. This is intended for the creator of the game, so spoilers ahead.

Presentation

The music is great and fits great with the themes and aesthetic of the game. Visually, this game is beautiful and totally aesthetic. The characters are very well done. The title screen, environments and even the chapter titles are incredibly stylish. Not to mention it's a 3D game, which is even more impressive for a game jam. Making a graphically ambitious game often means sacrificing some readability and gameplay, but this is mostly not the case with good contrast and colors used for the important elements. I'll elaborate on this later...

Dungeons

The basic idea is that you have to explore a procedurally generated dungeon, completing objectives such as rescuing lost and terrified schoolgirls, all while dodging a barrage of knives and running from ghosts. The enemies are really relentless. They keep spawning all the time, so you have to constantly move and shoot. If you are carrying a girl, your movement and firing speed is slower, so that's another thing you have to manage. Right off the bat, it feels like you picked the hardest difficulty in the menu (not "Hard", the one that's usually below it). But no, this is the default difficulty. I'm pretty sure most people would not a game this hard, but I found it pretty fun. Overall the movement speed feels a little slow though.

I'm not a big fan of procedural generation. But in this case it works well, because the game is designed around it (exploration, hide and seek mechanics). No complaints there.

The ghosts can move through walls, which is something you have to play around. Sadly this also means you can get hit unprepared if you're standing too close to a wall. That's not fun.

Boss fights

The boss fights are where I feel the enjoyable difficulty starts turning more into frustration. I'll start with the biggest problem: The high bullets. When you have to dodge bullets that are higher than ground level, the "2D" shooter turns into a 3D shooter. You can no longer use intuition to dodge the bullets, and how you have to dodge them changes depending on the perspective and relative positions. I got hit too many times by these, and it didn't feel fair. Because it has similar boss fights, I'll tell you how Nier:Automata does it better. In Nier, you have a full 3rd person camera, which lets you adjust your perspective to understand where the bullets are. The bullets are also much larger and move slower in general. I don't know if this type of gameplay can be done right in a fixed perspective 3D game, but right now the high bullets are a big problem.

Another problem is how hard it is to hit the boss. Since the player has to aim with the mouse, it would be fair to give more leniency with how accurately you have to aim.

Yes, I did ragequit on the final boss. Like the rest of the game, the difficulty is cranked all the way, but there are also the aforementioned high bullets, and a few times where a bullet can spawn inside you, giving you no time to react. Every time you die you have to walk the same path again. That's too much. I'll try it again before giving my final rating. (Edit: I beat it!)

Verdict

It's brutally difficult, but it's also fun, polished, and well paced for the most part. With some fixes to the difficulty, this game could really stand apart.

Finally, you wanted me to answer some questions.

How do you feel about the 3d movement/shooting mechanic?

It's good overall, but lacks the precision of 2D and has a few major issues. See above.

If you have to play procedurally generated chapters repeatly, do you feel if it's repeative?

See above.

If it's a local multiplayer game, do you think it's better to keep in one view and it should split to multiple view?

Local multiplayer would be nice, but I would improve the gameplay and add more content first. I'd probably prefer splitscreen, that way you can have more freedom and collaboration between players.

What elements do you want to add in the game?

It already feels like a complete game, so I would focus on improving the elements that are already there.

Cheers!