The description for this system was right, this book is cursed. I picked up this book because I was curious as a big fan of creepypasta what sorts of ttrpgs were available, and i've got very mixed feelings. For starters, the advice given for running horror sessions and the tools provided for customization of your own horror villain are excellent and extremely flavorful, useful even if you aren't intending to try and run this system. There is also a very interesting system for a character's shift from naivety into madness which I think is a great way to handle reaction to horrors and I will definitely be stealing it and tacking it on to other systems when I run, so all respect goes to the author for that.
Unfortunately, there are some decent reasons why you indeed shouldn't run this as the book presents. First and foremost is the unique dice-buy system advertised in the description. I like novel ways to resolve dice tests, but this is unfortunately a case where I understand why I haven't seen a system like this used anywhere else. I won't describe the system in detail, but suffice to say that it makes doing simple tests vastly more complex than it should be, and really slows things down. To make sure I wasn't crazy, I recorded how long it took me to resolve a simple test using the methods from various popular systems. The D&D 5e method of roll 1d20 add modifiers took me an average of 3-4 seconds from picking up the dice, rolling and totalling, and then comparing to a difficulty class (although a few seconds would be added in-game for communication). Using the Vaesen method of a pool of d6, it took me about 5-6 seconds, and the same goes for the Call of Cthulhu d100 method. This system's test rolling method took me around 20 seconds, and I didn't even get the most arduous roll possible. This time is only likely to increase by significant multipliers for players new to the system or who are not good at mental math (which to be fair, is most people). Additionally, this roll method is used for almost everything, and contributes to major slowdown in play and at times a loss of tension due to players needing to bust out the calculators and remember what dice explode into what other dice and which dice go with what stat, etc. It's not the end of the world, but it is kinda just a worse method than any other horror system you're likely to pick up.
That all being said, this book contains some excellent tools and advice for horror DMing of a level of quality that I haven't seen even in some of the big-name horror systems I mentioned in the previous section, and so if you're a DM looking to run some modern horror in the creepypasta style and car spare the small price, it's a very worthwhile read to serve as food for thought.