Even when dipper ensured willow would be born, he asked something in return, even when Henry became the woodsman, the cultists paid the bill so to speak. When willow nearly died giving birth, what did she owe Alcor when he saved her?

Nothing. Stan and Henry paid that bill, as it were, for her, with six months of their lives each.

And when it comes to his niblings (and the rest of his family as well, but definitely his niblings), whatever shortfalls there may be in a deal, Dipper takes that on him, despite what his demonic instincts may be yelling at him to do. That being said, whenever Mabel and Henry or the triplets make a deal with him, they try and offer an even recompense, because one sided deals do take a lot out of Dipper.

TLDR; what Stan and Henry offered to save Willow’s life was enough, but even if it wasn’t, Dipper would have made it work anyway because Willow is his niece and he loves her

…Apparently there’s a stomach-faced duck in gravity falls (it’s shown in Journal 3 during the Scary-Oke ep), so I wouldn’t be surprised anymore if there was something akin to Brian the Organ Duck on the show. Oh god…I want there to be a Brian on the show. Transcendence AU what the fuck have you done to me to want a fucking demon made of organs that looks like a duck aPPEAR ON A KID’S TV SHOW????? WHAT WITCHCRAFT WHAT

THIS MAKES MOD C SO HAPPY YOU DONT EVEN KNOW