I do enjoy reading some few VNs, so I might be a bit harsh on this.
Overall, the story itself is pretty solid so that's good. However, it feels off at first, only until 1/4 did I realize there was no BGM? Or is it just me maybe? Anyways I did put my own BGM from Youtube "First Anniversary Login Menu Theme | Girls' Frontline 2: Exilium" and it does fit (Don't actually use this specific song in game lol). If there really isn't any, I would say you can take some few non-copyrighted songs from DOVA-SYNDROME and find from the top 100 playlist.
I only finished the game once, as I don't know if there are actually multiple routes here as VNs tend to have their own flowchart. Still, I would say you managed to do a great job on the story telling, I actually kinda liked it as I go further in. I can definitely feel the inspiration at first, which was The World God Only Knows, and then add in elements from Date A Live.
Respect to you also for making your own CGs using the models, although there are some few lacking as what the other comments pointed out. But still its understandable as it's a Game jam so time is short.