Summary: Bill's playing super'hero', and the twins are playing with him!
A brown haired fourteen year old boy sat in a room. A rope wrapped around his chest, and a second rope was wrapped around his wrists. His wrists where behind his back, and his ankles were tied together too.
Nearby, two other people fought. One of them was female, and looked almost exactly like the boy. The other...well, he looked like neither of them. One couldn't even be able to tell his age by looking at him. He look...somewhere in between fourteen and seventeen.
The odd boy had yellow-blonde hair, and odd eyes. Yellow with black slits for pupils. He wore a yellow shirt with a brick pattern on it and black sleeves that went down to his wrists. His pants were black and he also wore black shoes. The boy had a black top hat on his head, and a black bow tie on his shirt.
The 'boy' was none other then Bill Cipher, a dream demon.
The room the three were in didn't exactly...exist. The twins and Bill were in Dipper's mind. He didn't exactly approve of it. That's how he ended up being tied up on the floor.
"I will defeat you! For I am Sparkle Sparkle!" Mabel yelled. The girl was pretending to be a super villain.
"No way! I will defeat you, because I am Madness!" Bill was also pretending to be a super villain. The two 'villains' were fighting over who got to keep Dipper captive.
"Okay, guy. Seriously. Untie me." Dipper said plainly. He was beginning to loose hope. Could anyone rescue him in his mind? Probably not. Bill had taken away the twins' power to control the mindscape for the game.
"Silence Kirby!" Mabel yelled. Realizing what she said, Mabel covered her mouth and her eyes widened. Dipper's eyes widened at the name 'Kirby'.
Bill hesitated. "...what?" Was all he asked. Bill was a dream demon, yet...he wasn't allowed to know names. The only names he could know, where that of whoever summoned him, and neither Dipper or Mabel had ever summoned him. That's why he called them Pine Tree and Shooting Star when they first met, and 'kid' all of the times after. Bill did know their names now, but he wasn't allowed to say them.
Dipper squirmed and bit his lip. "Err..." Both Dipper and Mabel knew that Bill couldn't say their names, and they had agreed to never summon Bill. Dipper had his own personal reasons, mainly he didn't want anyone to know his real name.
"Dipper's real name..." Mabel began. Dipper groaned and shook his head, clearly not liking that the dream demon now knew his real name.
Bill's eyes widened in understanding. Then, he began to laugh. "Y-your r-real name...HAHAHA!" Bill tried and failed to speak.
"Oh shut up, you can't even say my name!" Dipper snapped.
Bill was too busy laughing to hear anything. Slowly, Mabel began to laugh too.
"You guys!" Dipper tired. The only response was laughter.
"T-tell me h-his full name." Bill said through laughter.
"No!" Dipper yelled.
Mabel grinned. Her brother was tied up, he couldn't do anything. "Kirby Ezra Pines."
Dipper groaned. "Great. Just. Great."
After a while, both human and dream demon stopped laughing.
"Great. Now can you untie me?" Dipper asked impatiently.
Bill grinned and ran forward, grabbing Dipper and running away with him.
"Princess K.E.P is MY hostage!"