If you're interested in polyamory/monogamy and negotiating incompatible sex drives and relationship orientations, with a backdrop of magics and quests - rejoice!
I'm not much for the author's descriptions of his own work (stop calling this character a nymphomaniac bisexual with a split personality, I disagree with your interpretation of her and you are pathologizing needlessly and oppressively). I also didn't especially love the first few chapters (the ones in this book I'm reviewing), as they use the tired "awkward male protagonist likes girl" schtick, and there's a fair amount of sexist and homophobic characters. Plus, the very first page is about how sex is a universal, integral experience, which, asexual erasure much.
BUT - as the series progresses, it turns out that this annoying male protagonist was mainly a plot device to (re)introduce the real main characters (since there is actually a lot of canon backstory which exists in "Book 0," the older and less-pretty webcomics), and he gets rightly background-ed. The homophobia and sexism are predominantly symptoms of the small town we start out in, and we leave it soon enough. I can write off the "sex, it must be important to absolutely everyone" bit as part of the character's overexaggerated stage show.
And, I fell in love with the characters, their dynamics, the exploration of their compatibility, and with the world-building and sorcery and plot.
I was worried about the "hypersexual/nymphomaniac bisexual non-monogamous girl" trope, but the actual representation of her character is very well-done and nuanced. The way she talks about her perspective on things like sex, nudity, and relationships sounds like the things a pansexual non-monogamous person with a high libido would actually say. She doesn't feel over-exaggerated or (too) over-sexualized, and she is presented sympathetically.
She is juxtaposed well against her partner, and both of their feelings and belief systems are treated with respect and carefully explored as they try to negotiate a way to stay together. Throughout their adventures, they continue to struggle and have genuine, unfabricated conflicts. They have meaningful discussions with other characters about honesty and compromise, about the nature of sex and what is "natural" or "disgusting" - and all of this flows with the adventure narrative.
I am seriously invested in this webcomic and the ongoing relationship between two characters who love each other intensely, have fundamentally different beliefs about relationships, and are fighting to stay together (along with fighting some serious enemies and some moral battles - sometimes with very cool magic). Hardcore recommend.