Here’s a suggestion. Never let my mind run COMPLETELY rampant around parodizing YA novels. Because this sort of shit happens:
No, that was not a typo. A Lichenthrope - A literal Half-Man-Half-Lichen, which is somehow still attractive in spite of being some kind of symbiotic terror. She accepts this without question while he is torn and tormented between his algal side (that just wants to, understandably, veg out), his fungal side (which just wants to spread its fruiting bodies everywhere) and his human side (who hates both of the other sides and is really getting tired of being the brain of the outfit).
Generic McMeaningfulname thinks she can help him and shine a light on his dark embittered soul. He seems to warm up. It’s actually the fungi. A haphazard kiss later, she is infected with fungal spores and functions as a gigantic disease vector for a fungal zombie apocalypse, corrupting the town and all it holds dear. She, for some reason, remains mostly unaffected. She ends up being horrified at what she’s done. Lichenthrope emos out in the corner. End book one.
Book two! Three years later the entire Alaska area is a post-apocalyptic nation of survivors and mushroom zombies, kinda like The Last of Us but not as attractive. Our intrepid female protagonist is fighting a losing battle with her own fungal infection, the sparkle-lichen isn’t anywhere to be found because he’s gone off to attempt to fix the mess he created and hasn’t returned yet. And this is where we get the secondary love interest because those series ALWAYS have one of those. ALWAYS.
And guess what? It’s a fucking were-reindeer who is torn between his obsession with the female protagonist and the fact that reindeer eat trip-out mushrooms and SHE SMELLS DELICIOUS (and trippy).
Somehow the (marginal) plot manages to shuffle between survival horror and romantic tension until the lichenthrope returns with his entire fucking clan (of which we knew nothing until now - after all weren’t we led to believe his curse was a unique one?) who apparently can cure the entire region by some kind of hyper-vaccine derived from their algal side - except that this leads to a bitter war between them and the were-reindeer because NATURAL ENEMIES HURRRRR.
Book 2 ends when the male protagonists bite each other simultaneously, the female protag jumps in between them and gets impaled on the were-reindeer’s antlers. DRAMA!
Book 3 starts off with a fucking dream sequence (clearly) as the three protagonists are recovering from their near-lethal injuries at the end of Book 2 - where they are still blaming each other for all this mess and [Generic McMeaningful] tries to get them to calm their tits, even if she is the only one in the entire dream sequence which has any to speak of (coincidentally, they’re probably mushroom caps under those torn fuckedup-chic clothes). A continuity nod to the female protagonist smelling delicious and trippy as balls is noted. Their argument is interrupted by a vision which tells it like it is and sends them back into the real world to get their respective factions to settle their differences and fight the true enemy that would destroy them all - a dystopian government force run by an obvious Sarah Palin analogue who probably hunts werewolves from helicopters. In the final battle the were-reindeer clan invokes an ancient ritual to summon the spirit of Santa Claus while the Lichenthropes attempt to stop the fungal zombie waves - or at least to convert them into an army to fight the helicopter-flying bible-thumping shotgun queen. It appears that the clash of the century is about to happen when the whole thing is brought to a screeching halt by a whole fleet of lawyers which proceeds to vroom into the scene in exceedingly expensive looking cars and serving the entire fucking battlefield a cease-and-desist, scattering them.
Left to her own devices, the now nearly-completely-shroomified female protagonist unleashes a psychic scream that reaches out to anything that has ever come in contact with the fungal parasites, detaching them from anything and anyone that carried them, linking them together into some kind of ginormous world-tree shroom and provides eternal shelter to Lichenthrope and Were-reindeer alike. The male protagonists end up, inevitably, together - because clearly they hate each other’s guts but they were brought together by their love for the female protagonist and respect to her sacrifice and that TOTALLY means they’re going to be completely gay for each other. That’s 100% true. Fangirls on deviantArt who think they’d be ttly cute together said so liek omg!
As peace returns to Alaska, we are treated to the final shot, where a vague news story about the events of the last three books is shown in a completely different country that has absolutely nothing to do with the plot otherwise.
"Thank fuck all this dystopian future bullshit only happens in America while the rest of the world is safe." says a man to his wife of many years.
"Yes, dear." she says, turning to the camera to reveal a conspiratory grin and her face promptly falls the fuck apart to reveal the head of a fanged moose,
ROLL CREDITS (Because there’d inevitably be movies with a shitty sequel hook and they’d probably split the third book into two movies because merchandising)!
Also note that while romantic tension is rampant between just about everyone and their goat (and if there isn’t, the fangirls willl indubitably find some) no one ever actually gets laid. That is because most fungi either reproduce asexually or have a million different sexes and the YA novel world is not entirely ready to explain THAT much diversity to its readers.
There may, however, be some pretty explicit descriptions of meiosis - because, after all, sex cells.)