This is a pretty good game. The adult content is so-so, mainly due to the render style and middling frequency. What's there is good if you get invested in the characters, and the girls all look good enough. The overarching plot falls off a bit in my opinion - its starts off more focused and tense, as the MC is in a struggle for his survival from day one. The latter part of the first arc is where i think things start to go wrong - characters start doing things which are just too illogical, and things start to devolve into poor hollywood writing. Half of the problems and conflicts which end up occuring could've easily been solved with communication. I don't expect people to behave perfectly rationally of course - who would - but as readers we are asked a bit too much to suspend our disbelief at some of the frankly retarded decisions made by some of the characters. This is all redeemed by the setting and world building though - the core premise, demon-like creatures being bound to humans in an urban fantasy world really hooked me and kept me invested - this could be in part due to it hitting a number of taste points for me. Furthermore, the characters are all good to very good - dialogue quality and general prose quality were a bit mixed, and there were a few typos and grammatical errors I caught, but the most important challenge of creating characters which actually have distinct personalities was passed easily. Ultimately, the two most important things to nail for a story based VN, in my opinion, are characters and world building - I can forgive flaws with production value and plot if the rest of the meal is good enough. and in Companion of Darkness it is. In short I recommend this to anyone who feels like playing something which will demand a bit more of your attention to actually read it and appreciate what's there; this certainly isn't one for skipping to the adult scenes.
If there was an option to rate 4.5, I would've done so, but I know what kind of slop gets a 4 on this site so a 5 star rating it is.