Note: I was provided with a free review copy of this game by the developer. All opinions expressed here are solely my own.
The multi-route mystery VN is not a format easy to pull off properly and for that reason not many EVN developers even attempt to tackle it. It requires creating a number of paths and characters, all interesting on their own and complementary to each other, while also keeping the overall quality high enough to motivate the reader to go through all of it in order to piece together the overarching story. This is both a challenge from the writing perspective and requires a fairly substantial amount of content to communicate the mystery effectively – usually, more than an average Western visual novel can provide with the humble resources at its creators' disposal.
Still, all this makes exploring the few examples of such games done right by Western devs that more interesting. SoulSet, developed by NoBreadStudio and released on Steam in late 2016 is a particularly “orthodox” implementation of the formula, with every route and ending (including bad ones) adding to your understanding of the story and culminating in an unlockable “true route”, which resolves the crucial mysteries and tie all the previous paths together. It’s also, as I will try to argue, a damn fine game that positively stands out in the EVN market, in a few ways.