Challenge #01258-C163: Demonic Corruption

If you have encountered the Transcendence AU of gravity falls, please use it in today's challenge. (it's a great AU you'd love it and half of it was written long before it all came true in the show)

"The idiots that read mysterious cave writing/old books aloud as they go or while they translate and accidentally summon things coughAlcorcough by being just that monumentally dense. Or, small children who still read by carefully sounding out syllables getting into the collection of rare books and yeah you see where this is going." -- Gallifreya

[AN: Yeah, that's a pretty involved AU. Also: whoops, I accidentally did this now instead of 15 days from now. Derp]

Once upon a time, there was a dying demon. He tried to find shelter from his demise inside the mind of a mortal, without opening the doorways properly. Once upon a time, the demon died, and the mortal was never the same.

It was an old story. Told amongst the Pines as both family history and cautionary tale. How a twin brother and sister defeated the strongest demon in the mindscape, and how the brother paid the eternal price. Neither human nor demon, neither real nor unreal. And how knowing his true name could save your mind, body, and soul.

They were fairytales to Lalli. Old stories. Ever since the Angelic Intervention, demons had not been seen in the physical plane. They still taught Defense Against the Dark Masters in school, but hardly anyone took that seriously, any more.

Nevertheless, she loved the old books. The smell, the way the pages crackled as they turned. The weight of them. And the taste of the old words on her tongue as she painstakingly read them.

The Pines House was busy and crowded and nobody seemed to care that a small and quiet child was reading to herself in the library.

They would mind soon enough, because in the middle of the sweater patterns was a spell guaranteed to summon the family demon of legend.

He looked almost like a regular human in a top hat and tails. There was no sign of bat wings or fangs. And his smile was pleasant enough. The place to look, to see that he really was a demon, was his eyes. They were slotted like a cat's.

"Well, hello again, shooting star," he murmured. "It's been a long time."

Lalli should have been afraid. Demons were bad news, everyone said. But this one seemed... familiar. Like a dream she'd thought was forgotten. Or an old coat coming out of storage after months of summer. Words came out of her from that forgotten dream.

"Heya, Dippingsauce," she whispered.

The smile faded away into an expression of shock. He whispered, "Mabel..." and pressed a finger to her forehead.

Lalli's brain felt... itchy. Old dreams of past lives flitted through her head. Especially that one, long-ago summer when the world changed. Those echoes were the strongest, so Lalli reached out to boop a demon's nose. "Bwap," she giggled.

"Yeah. That's right," could a demon cry? This one had moisture in his eyes. "I'm gonna make sure you have a good life, kiddo. Free of charge. Just... be as you as you can."

"Okay," said Lalli, "but you gotta be good, too."

He offered his hand. She shook it.

And that was how a four-year-old began the long journey for a demon to become an angel.

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