Twin Souls

Twin Souls is a trashy romance series that exists in-universe within the Transcendence AU that gains quick and massive popularity- enough to even receive its own movie adaption. In the future, the series would come to be regarded as a classic. Unfortunately for Dipper, elements of the story would become irrevocably intertwined with other, more reliable (or less disgusting) Alcorian lore.

Characters

Its characters are loose interpretations of Alcor, Mizar, The Woodsman (Henry), Gliese (Willow), and others generally associated with the previously mentioned people.

Alcor ('Al')

He's not evil- only misunderstood :(. On a side note, unlike the real Alcor, who is completely asexual and only interested in platonic relationships, Twin-Souls-Alcor is completely head over heels for Mizar. Mizar is initially unaware of his demonic nature, as he took human form to attend high school. He's described as a quiet, mysterious boy who sits at the back of the class.

Mizar Singleton

A human high school girl who moved from California to Gravity Falls, only to immediately fall madly in love with a demon, although she doesn't know it. Mizar shares several classes with Alcor. She's an only child, and has a love for animals.

The Woodsman

A demon with which Alcor has an illicit affair and eventually assigns as guardian to Alcor and Mizar's lovechild, the shapeshifting demon Gliese.

Plot

The series is notoriously inaccurate, portraying Alcor and Mizar as high school lovers a la Twilight. There have been several different incarnations of the first story; in the original, Alcor is paired with Mizer, but in later series he is shown to have affairs with The Woodsman, lesser demons and humans, and occasionally Bill Cipher.

Fans

Despite all evidence to the contrary, the majority of its fans are convinced Mizar and Alcor are actually an item, which drives Dipper absolutely insane, and inspires endless amounts of teasing from Mabel. The ship is almost as embarrassing as the also-popular Alcor/Woodsman ship.

Though few and far between, there were a few fangirls of the series have been known to summon Alcor solely for the purpose of asking him questions related to its canon, much to his irritation. Not to mention the ones that actually want to be with him (shudder) by using lines of cheesy dialouge and "romantic" settings near their summoning circles.

Alternate Twin souls

Twin souls also exists in the Friends with Tax Benefits AU of the Transcendence AU

First thing to consider is that Mabel did operate as Mizar alongside Dipper as Alcor for years before the turning point of fwtb. Mizar will be a known name - perhaps there’s even been an early book or two about them as in canon universe.

Then, to the rest of the world, Mizar simply vanishes. No explanation, not even a precisely pinned down time…people just eventually notice that she’s no longer showing up to bash down cults at Alcor’s side. Survivors report that he acts either alone or with a tall man at his side, a man he calls Sarva.

Then there’s the ring he takes to wearing, and speculation abounds, and from that rises a new book series. Perhaps it’s not called Twin Souls, since it’s not about the twin stars Alcor and Mizar - it’s about Alcor and Sarva, and whatever it’s called it’s just as much a terrible steamy romance trash series as the original universe’s version, complete with magical demony mpreg to explain Gliese.

Then, some time after Sarva becomes the Woodsman and that’s recognized as a thing, the writer comes out with a new book, one that explains the vanished Mizar in more depth than the previous occasional mentions that vaguely implied she was a love somehow lost.

In this book, Mizar is the villain. She’s a demon like Alcor, once involved in a dark romance with him, until they separated and he found his one true love Sarva and became a special not so evil demon unlike all the others. Mizar wants him back to his former evil self, just like her, and seeks to tear him and Sarva apart by any means necessary - even if it means destroying Sarva entirely. 

In this book, she is the one who turns Sarva into the Woodsman by means of a curse. “You want to love a human? Here, now he’s human no longer!”

All in all, it puts a rather dark spin on any subsequent fanfic ships involving Mizar, barring those who use the ship to turn her good of course.

It also gives Dipper an entirely different reason to hate those books, though whether this results in blazing rage or absolute despair is up in the air. Both, perhaps, in various stages. Having his name and reputation taken and twisted into the trope of the sultry passionate lover is one thing. Having his sister’s name and memory taken and twisted into a jealous, shallow thing of evil is quite another.

Trivia

• Twin Souls is a blatant Twilight and fifty shades of gray joke.
• Mabel is rarely deterred from it, and actually finds it hilarious.
• Most Mizar reincarnations find it amusing. Bentley Farkas is the first to be as disgusted with it as Dipper.
• Mabel likes to find copies at the library or fanfiction stories online and then read them aloud to her brother and husband. She often purposefully finds the Alcor/Woodsman ones.