You've read the manhwa and watched the anime – why not read the novel as well? Possibly because it's 888 pages long. Like the BTS novel 7 Fates Chakho, Dark Moon is an exercise in Wattpad madness – a story that ties in with a K-pop boy band and casts them all as various supernatural versions of themselves in a complicated story. This work is based on the guys of ENHYPEN, and unlike the BTS novel, there's also a reader-insert character, a girl named Sooha, who ends up tangled up with the boys in various plot-important ways while also having a romance with Heli, the ostensible main guy. It's the sort of book that's enjoyable while not actually being all that good.

It also has some distinct differences from the manhwa, which was released in English first, also by Ize Press. The main change is that Sooha isn't a new transfer student when the story starts – she's been at Decelis for a month as a member of the day class. That, as manhwa readers and anime viewers are aware, isn't a designation at Decelis in the other versions of this story; the school is night classes-only. While this does make the similarities between Dark Moon and Vampire Knight more obvious, it also works better in terms of setting up the supernatural elements. By having day and night classes, there's a mystique created around the night students, especially since the main sport is “nightball,” which appears to be rugby played at night with glowing balls and goal posts. This mystique is important because Sooha, in this setting, doesn't have the virulent hatred of vampires that she does in the other variants. Chris, her childhood friend, is completely absent from the story, and Sooha is simply self-conscious about her preternatural strength rather than actively attempting to distance herself from vampires. While this doesn't do much for the tension in the romantic subplot, it does make Sooha more comfortably part of the group, and since that's the fantasy the book is selling, it's a good change.

Like the anime and manhwa, the main plot centers on a group of predatory vampires with an unclear motive. The good vampires and the werewolves are working to stop them while trying to make sense of what their goals are – and what, if anything, they have to do with the dreams the entire group has been having. In their dreams, they seem to be living a different life, where the seven vampires are knights protecting a princess. As the story progresses, it becomes clear that things did not end well for any of them, and part of what drives them is the idea that this time, they need to get it right. If you're familiar with the overarching story of Pretty Guardian Sailor Moon, you'll find this reminiscent of that work to a point, although that's a parallel better shown in the comics.

The cast of characters is huge, with fifteen named characters as the primary protagonists plus three named villains. It's a lot to keep track of, especially since, unlike in more visual storytelling methods, we don't have illustrations to help differentiate who's who. There are photos of the members of ENHYPEN as their characters at the start of each chapter, but unless you're already familiar with them, it doesn't help all that much. Fortunately, the writing is decent on this front, and everyone has a distinct personality. Sooha is the least developed, but as she's meant to be the reader-insert, that does make sense, and she does just enough not to feel like a damsel in distress.

As the book goes on, it falls apart a bit. The writing in the final 150 pages isn't nearly as tight as the earlier pages, and some jumps in the plot make it feel like you're missing something, which is a major problem when the book is nearly a thousand pages; it should be enough to tell a story that feels complete. The general impression is that the writing is simply crumbling under the weight of the plot and characters, and it is worth mentioning that for what could have been a very cringey tie-in advertising a boy band's discography, it tries its hardest to tell an interesting story. It's easy to get pulled into the narrative, and it mostly suffers when it feels the need to emphasize that all of the boys are “brothers” and the strong bonds between them. These sections often feel like overt marketing, an attempt to sell an image rather than tell a story. While you can't quite blame them for this, it's still a detriment, especially if you're not reading this out of love for the band.

Dark Moon: the Blood Altar is, like so much Wattpad fiction, the literary equivalent of a Twinkie. It's fun and easy to consume as long as you don't think too hard about the ingredients. If you're a fan of ENHYPEN, the glossy, full-page photos of the members are an extra draw (if you're not, they're a bit of second-hand embarrassment, because wow, they are cheesy), and it's hard to fault Ize Press' edition, a hardcover weighing what feels like two-to-five pounds with a ribbon bookmark. If you like the story in its other forms, this is a fun addition to the mythos, but be prepared for something that isn't likely to stick with you for long, despite its length.