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Dipper was animatedly asking about Mabel’s interdimensional adventure, and she happily answered his questions. He was so glad to have her back. It felt like hours had gone by since she was sucked into that rip in space-time. But she was back home. She was safe.
Best of all, with that last rift sealed, a horrible mishap like this couldn’t happen again.
But as Mabel tucked her hair behind her ear, Dipper noticed something strange. Her cheeks seemed almost…narrower? And the little tuft at the top of her head seemed a little sharper. She looked over at him, and he saw a flicker in her eyes. Something wicked. He stepped back. She smiled innocently. “What’s with the look, Dipping Sauce?”
“You seem…different.” He shook his head. “Never mind. It’s been a long day.” Then he added, half-joking, “maybe we can put on a movie marathon tonight. I’ll even put on Dream Boy High first.”
“Dream Boy High?” Mabel asked, perplexed, and Dipper turned to face her again. Something wasn’t right.
“…yes. Your…favorite movie?” Dipper prompted in a slow, careful voice. Mabel’s face suddenly lit up. But it looked more like she’d suddenly remembered her lines in a play. The words she spoke weren’t her own.
“Oh! Oh, of course! Dream Boy High! I love that movie, with all the boys and the—”
“What did you make Grunkle Stan do after he lost the bet you two made earlier this summer?” Dipper suddenly asked. He knew that Mabel didn’t need a second to answer. She’d know it in her sleep.
Mabel quirked her head to the side. “Uh, write a formal letter of apology?”
Dipper shook his head, eyes darkening. The look he swore he’d never give his own twin sister. “I knew you looked a bit different, but I thought it was just wear-and-tear from interdimensional travel. You’re not my sister. Who are you?”
She smirked, examining her nails. “I didn’t think it would take this long, Dip Dop, but oh well.” She held her hand out. “Anti-Mabel. The pleasure’s all mine.”
“And none of mine,” Dipper growled. “What did you do to my sister?”
She shrugged. “I shot her out of an airlock.” She giggled. “You should’ve seen her face.” His whole body turned cold at the thought of Mabel hurtling through space, all alone…
That was the thing that Mabel feared the most, so for her to be all alone, worlds away from her family? That was a far more brutal twist of fate. He thought about what he’d said to her, mere moments she’d gotten sucked through that rift. He’d called her self-centered. At the time, he deemed it something she needed to hear, but what if that was the last thing he’d ever say to her?
Besides, he knew nothing about the multiverse beyond what his Grunkle Ford told him.
Now, he was staring at some sort of evil doppelgänger, an imposter wearing his sister’s skin. “You’re a monster!”
“Maybe,” Anti-Mabel said uncaringly. She truly was everything his sister wasn’t. “But soon, it won’t matter! My Mabel impression is spotless. In a few months time, you won’t even know the difference!”
Dipper wanted to throw up at the thought of her not only stealing, but living Mabel’s life. “It won’t work.”
”Won’t it?” Anti-Mabel’s lips curled into an ugly smile. “Tell me this, Dipper: do you think anybody would believe you if you said your sister was replaced by some sort of evil clone? They’ll think you’re crazy, bro bro!”
”Don’t call me that! You’re NOT my sister!”
He was aching for the loss of his real twin sister, and even more so for the idea that she thought she could replace her.
“You’ll never be Mabel, you sick freak! Never!” And he turned and ran. The forest warped and twisted as footsteps pounded behind him.
“You’re nothing without me, Dipper! Twins for life! TWINS FOR LIFE!” She laughed, high and shrill, but the sound was uncanny in a way that made his skin crawl. Like it came from something inhuman. He tripped, flipping himself over. He backed away from Anti-Mabel. Her skin had gone pale, almost blue, her eyes shiny, like a doll’s. As she spoke, it was as if her body housed two souls instead of one. “Nothing’s gonna stop me from having her life, Dipper. Not even YOU!”
Dipper bolted upright, heart thundering inside of his chest. The attic creaked as the house settled, and he looked over at Mabel, the real Mabel, peacefully sleeping in the bed across from his.
Carefully, he got out of bed, stepping over the attic’s creaky floorboards. He’d just check on her, just to ease his mind. He forgot when he’d gotten a full night’s sleep.
The covers had fallen halfway off, so he tucked them back around Mabel before turning to tiptoe back to bed.
Mabel’s groggy voice made him stop dead in his tracks. “Nightmare?”
So much for not waking her. “I’m okay, Mabel. Go back to sleep.”
Mabel sat up and switched the lantern on. “No way. You know I can’t sleep until I know you’re actually okay and not just saying you’re okay.”
Dipper sighed and plopped down, the mattress creaking. “Remember when you fell through that rift?”
Mabel nodded, understanding. “Was it her?”
“Yeah,” he said, sounding tired, older, like the experience had aged him thirty years. “She—she won. She left you out there, all alone…and there was nothing I could do.” Tears formed in his eyes. As much as he hated appearing weak, nothing scared him more than losing Mabel. He’d already almost lost her twice. Once to her prison bubble, and once to that stray rift.
Not to mention that there were more. If his uncles didn’t have the alien adhesive, he wasn’t sure what would’ve happened.
She got up and sat down next to Dipper, wrapping an arm around his shoulders. “She lost, broseph. She can’t hurt anyone ever again.”
“But she came so close,” Dipper said in a broken voice. “She almost left you trapped in that awful place, almost took over your life!” If Dipper didn’t know Mabel so well, he might’ve fallen for Anti-Mabel’s ruse.
“She did, but you and both know that she isn’t the worst thing we’ve dealt with. We fought cursed wax statues! We battled an army of gnomes! We took down Gideon’s stupid robot! Heck, we survived the literal apocalypse!”
“I know. I guess I’m just worried that one day, something bigger will come, and I won’t be able to protect you.”
“Listen, Dipper,” Mabel said, taking his face in her hands. “You are the strongest person I know. You helped take down that stupid nacho demon! Nothing, least of all a copy of me is gonna change that! You’re unstoppable!”
For the first time since he woke up, he managed to crack a smile. Maybe he’d see Anti-Mabel in another dream, but he’d remember what the real Mabel said. You’re unstoppable.
THE END