The synopsis make it sound much better than it is. It's very rushed, basically a found family speedrun, where everyone starts caring about each other real quick, even though they all treat each other very poorly. The MC and all the ROs are insufferable; just terrible people in general (Kenda is the only exception), and you never really get the chance to call them out on their bullshit. They all feel like they were written by an edgy teenager who thinks being an asshole is cool.
No RO is interesting or charming enough to warrant any sort of romance, specially since you need to agree with them on a lot of stupid shit to be able to romance them at all. The ending is very unsatisfactory, and there's also a sequel coming up at some point (I might read it out of morbid curiosity; wish me luck).
All in all, there's no point spending money on this, and you should only read it if you want examples of bad writing (which is a valid writing exercise, no joke).
tl;dr: it's not dark fantasy, it's edgelord teenage bullshit.