"Bill, please," Wendy pleaded. "Don't do this. I'll help you, I swear!"

Cipher continued ascending the stairs unphased. Dipper struggled to keep up and, when he finally lost his footing, the redhead lifted him by his arm and carried him along like a piece of luggage. The duo entered the bedroom and Bill slammed the door shut behind them. He dropped the boy unceremoniously on the hard floor, then marched to the center of the room, hands planted firmly on Wendy's hips, and began scanning every square inch of their surroundings for the journal.

The true Wendy joined them shortly after. The sight of the boy sitting on the floor, nervously watching what he believed to be her, made her heart hurt. He was clearly confused.

Dipper wrung his hands together, waiting patiently for the teen's next move.

No sign of the journal. Bill huffed then began ransacking the twins' belongings.

"Wendy?" the boy asked. "W-what are you doing?" He received no response. "Are y-you looking for something? I…" He unfolded his hand and lifted the sealed condom over his head. "I-if it's…Grunkle Stan gave me one."

The demon looked back at him, hoping the 'one' in reference was one of the three journals. When he saw it was merely human garbage, he resumed his search.

"Wendy?" Dipper stood up and approached the stolen body. "C-can I help? W-what do you need?" He reached out and touched her shoulder.

Bill swung an arm at the unexpected contact and sent the boy flying backwards onto Mabel's bed. Dipper gasped in turn, then stood from the bed, utterly confused.

The search was hopeless. As much as he hated to admit it, Cipher knew the boy was too smart to leave it lying around. He needed a lead. He turned Wendy's body so it faced Dipper once more, and stretched a forced smile onto her face.

"Dippy," he said. "You would do anything for me, wouldn't you?"

Dipper hesitated. The sudden shift in her demeanor set off alarm bells in his head, but his body demanded he stay on her good side. "I…of course."

"Could I see that book of yours? The journal? There's something I need to check. I…I saw something the other day in the woods, and I was just curious if the author had written about it."

Once more, he rubbed his neck in nervous frustration. "I-I would but it's just that…I shouldn't. I'm not supposed to trust—"

"You don't trust me?" Bill curled Wendy's lower lip and pouted.

"I do! It's just that…the journal, it's…there are things that want it and…I have to be careful, because if they were to—they might hurt someone I l-l-liked to steal it and—"

Bill tore Wendy's undershirt off and tossed it aside.

Dipper's jaw dropped.

The true Wendy dove in front of her corporeal form in a desperate, ineffective attempt to shield her chest from the boy.

Dipper was wholly entranced.

Cipher rolled his eyes at the predictability of human nature. "Dip," he continued. "I have an offer." The boy nodded dumbly in turn. "I'll give you something, then you give me something. How about I make you feel good, then you can show me the journal for a quick minute?" More thoughtless nodding. "Cool, dude." This would be easier than he thought.

The demon lifted the boy off the bed and stood him up, then dropped down onto Wendy's knees.

"What are you doing?" Wendy screamed.

Cipher ignored this and continued. Dipper continued staring at the stolen breasts as Bill slid the girl's nimble fingers along the waist of his shorts. With a quick tug, they and his underwear fell to the floor.

At this, the trance broke and the nervous, flustered Dipper returned. He scrambled to cover himself.

It was now Wendy's turn to stare, though the boy had no way of knowing. She watched the scene unfold in silence despite her welling fury. Something inside her wanted to see it happen.

Bill grabbed Dipper's wrists and forced his hands to his sides, exposing his erect length in all its glory. The sight ignited a hot passion in Wendy but had no such effect on the demon; human sexuality was a concept entirely alien, and he only ever employed it to reach an end.

And so too would he here.

With one last piercing glare at his trapped victim hovering overhead, Bill leaned forward and wrapped her soft, warm lips around the boy.

Dipper and Wendy gasped, both in disbelief that this was truly happening.

The sensation was overwhelming and Dipper's knees immediately gave out. Bill held him by the waist with Wendy's hands effortlessly, continuing his work without missing a beat. His ploy was working. With every second, the fog in the boy's head grew thicker—given another minute, he would be willing to jump from the roof at Bill's command. He was putty in these borrowed hands.

The true Wendy watched, equally enamored and enraged. The fire of passion butted heads with the heat of hatred in her, paralyzing her with indecision. Not that she could fight this. She was helpless, as much at Bill's mercy as Dipper.

The boy was nearing his limit, and his moans made this well known to the other two in attendance. Cipher stared at his victim's face over the rim of his glasses, watching intently for the right moment to withdraw, to leave him in all-consuming agony at his lack of release—the perfect state in which to bargain for the book.

Dipper rapidly approached this point and, wanting to see the expression of his long-time crush as she drained him, he looked down and met his eyes.

His…eyes. Not Wendy's eyes. They weren't green. In fact, they weren't quite human…they were…

"Bill?!" Dipper shouted. He climaxed despite himself, grunting and kicking hopelessly in Cipher's unrelenting grip.

The demon bit down on his manhood and cackled in delight. He may have missed his window of opportunity, but he had his delicious consolation prize: the delectable mental anguish of his foe.

Wendy gasped. She wanted desperately to help, to tear the monster off him. But what could she do?

Finally regaining his breath, Dipper shrieked in response to the teeth gnawing at him. Bill offered no reprieve. The boy fought through the pain and called out, "Wendy! Wendy, if you're here—if you can hear me, I—argh!" He choked back tears. "You have to find a vessel! You can talk through a—ah—a vessel! Mabel's puppets! Use a puppet! Aaahh!"

She dove for the pile of puppets beside Mabel's bed and, sure enough, she was able to pick one up. She seated it on her hand, and spoke: "Dipper! Dipper, I'm so sorry! I didn't know—"

"Help," he squeaked.

The puppet's head balled into a spherical lump as Wendy's hand closed into a fist. It shot through the air, a complete blur, and slammed into Bill's stolen face with a sickening crack. The demon cried out in surprise, releasing Dipper's member, and tumbled backwards onto the floor.

"Aha! I'll never get used to this pain!" he cackled. "How do you humans do it?"

They ignored him.

"How'd you get him out of your body?" the floating puppet asked. "How do we beat him?"

Chest heaving, Dipper asked, "Do you have any weaknesses? Are you ticklish?"

"No!"

"Anything? Anywhere I can touch that will make your body freak out and spasm?"

"Well…" Wendy gulped.

Dipper's face turned red. He knew it as soon as the question escaped his lips.

Bill stood up. "Look, just give me the book, Pine Tree. And this'll all be over. You'll never have to see me again, I promise."

"A-are you sure?" Dipper asked the puppet staring back at him. "Sh-should I?"

The puppet nodded. "Do it."

"As soon as he leaves, you have to take your body back. Don't give him the chance to take it again."

"Got it. Get ready."

"What could you possibly do?" Bill laughed. "Give it up, already! This body isn't as weak as yours. That old fool said it himself, she's too tough for your tricks. I ain't leaving 'till I'm good and ready, with that book where it belongs!"

"Now!"

The puppet dashed to Wendy's pants and tore the button loose. Dipper gripped the fabric on her thighs and tugged, dragging her jeans down to her knees. She wasn't wearing any underwear.

"What are you even doing?" Bill asked.

Dipper paused and stared at the fiery bush before him. Wendy wished she'd had the foresight to trim beforehand, but shook the thought aside. Noticing the boy's hesitation, she gripped the back of his head with the mouth of the puppet, then shoved his face in between her legs.

"Whoa! Turning the tables, are we? That's…" Bill shuddered. "Is this…so that's what that feels like."

Dipper quickened his pace, running his tongue across the warm flesh with urgency.

Wendy's body shook in response. Her legs weakened and her heart beat harder. "Hey! Stop that! It's—it's not funny," Bill whined.

He lifted one of Wendy's fists above the boy's head, prepared to strike. Before he had the chance, the puppet took him by the throat. The shock of being deprived air was unexpected for Cipher. He panicked in response, clawing desperately at the invisible hand gripping him, unable to peel it off with his corporeal hands. He could only tug at the puppet itself, to no effect.

Suddenly, the onslaught shifted in influence—the choking felt good. The lack of air didn't bother him. The strange tickling in his loins was welcomed. Something was growing inside him. He understood the principle, but had never experienced it. The two competing sensations somehow joined in harmony and met in the middle, warming the girl's body from within. His eyes rolled back in Wendy's head.

Her body shook violently as it came to orgasm, and her moans filled the room. Bill held on for as long as he could, but the sensation was staggeringly uncomfortable. Pain was something he had known. But this was in a new league entirely. The demon finally let go, and eagerly retreated back into the Mindscape.

The true Wendy took her opportunity and leapt back into her body. She was instantly met with her continuing climax, waves of pleasure crashing over her again and again as Dipper worked tirelessly on her hot, dripping sex.

"Oh, fuck," she moaned. "D-dude, it's m-me!"

The twin withdrew, her juices clinging to his chin and cheeks, bridging from her loins to his face.

"He's gone?"

"Yeah, he's gone." Wendy sighed in relief and sat up. "Y'know, you're not bad at that."

He blushed. "Thanks."

"No, thank you, Dipper." She pulled him close and hugged him tightly. "You saved me from that thing. I knew you would. As…as soon as he showed up, I knew I needed to come to you."

Dipper smiled. "But then…why'd you make a deal with him?"

"He…he said he'd worked with you before. I trust your judgment."

He rubbed his neck. "Heh…sorry about that. He tricked me."

"But you outsmarted him in the end."

"Mabel, technically," he admitted. "At her puppet show last week."

"So that's what that was all about! Dude, my dad is still pissed about that."

The pair laughed.

Then Dipper shrieked. The puppet Wendy had used was now clamped firmly on his testicles.

"Get him off! Get him off!" the boy begged.

Wendy pried the sock puppet from his body and gripped it in both hands, its jaw in one and the top of its head in the other. Bill's voice grumbled angrily from the fabric, unable to form words as she held its mouth open. She tore the toy clean in half.

"How do we kill this thing?"

"I dunno yet," he wheezed. He took a moment to catch his breath. "Still working on that. But he needs a vessel to interact with the physical world, so…" He looked back at the heap of reject puppets. Another was already squirming with life.

Wendy didn't hesitate. One by one, she tore each and every puppet until all that was left was a pile of frayed fabric scraps. The duo held their breath and surveyed the room, waiting for Bill to make himself known once again. But that moment never came. He was gone.

Her eyes wandered back to Dipper's body.

"Oh, Dip," she said softly. "You're bleeding."

Her own teeth marks dribbled blood at the base of his penis.

"You too," he said, pointing to her nose. "I…I think you broke it."

"Yeah. I meant to. Guess I didn't think that one through." She smirked.

The Pines twin pulled a first aid kit from beneath his bed and they helped each other clean up and redress before heading back downstairs.