Marceline floated on her back above the sofa in her house. She was holding her red axe bass and had spent the last couple of hours trying out new ideas for songs.

Suddenly, she stopped playing and turned her head around attentively. She flared her nostrils and a moment later, groaned. She floated over to her door and opened it just in time to see the Ice King swoop into her cave.

"Hey! What gives, Marceline?" The Ice King demanded, as soon as he was within earshot. "What's up with you hanging out with my GF?"

Marceline stared at him. "What? You've got a… Wait, you mean Bonnibel!? She's my girlfriend, Simon." She sighed.

"Pfft." The Ice King snorted. "Bubblegum's been dropping me signals for years now, she just needs you to stop messing up her head, girl!"

"Get lost, Simon!" Marceline warned, with a threatening edge to her voice.

She turned around to head back into her house.

"Well? Are you gonna stop messing around with my GF?" The Ice King called after her insistently.

Marceline froze in her tracks. Her eyes began to glisten with tears, but slowly, her misery was replaced with rage. With a furious cry, she turned around and punched the Ice King with her free hand. He flew backwards and his crown rolled off his head. As he crawled towards it, it floated off the ground and flew into Marceline's hand.

"It's been a long time since I last tried to do this…" She said, with a mad grin.

The Ice King stood up and ran towards her, but before he reached her, Marceline forcefully hurled the crown to her feet, seized her axe with both hands and struck the crown with it over an over again. Each strike was accompanied by a loud clang and flash of bright white sparks.

After almost five minutes of furious violence, Marceline collapsed to her knees and hyperventilated. Tears ran down her face and dripped onto the floor. The crown was deeply imbedded in the stone floor, but neither it, nor the axe had so much as a single scratch or dent on it.

The Ice King cautiously shuffled over to her. As he reached for the crown, Marceline looked up at him with fire in her eyes. Without even changing form, Marceline stood up, grabbed a handful of the Ice King's gown and lifted him off the floor with one hand.

"You would have encouraged me!" Marceline sobbed. "Helped me get ready for dates and told me what not to wear!"

"Geez Marceline! You're crazy!" The Ice King declared. "That dingus doesn't know what he's getting himself into!"

Marceline lowered the Ice King slightly. She furrowed her brow as she contemplated whom the Ice King could be talking about. Suddenly, her eyes widened.

"Ash? He set you up to this!? Why didn't he just come himself…?" She wondered aloud. A moment later, she dropped the Ice King to the ground. "Bonnibel!"

Marceline flew into her house. While she was gone, the Ice King walked over to his crown and began heaving on it, trying to pry it from the ground, to no avail. Seconds later, Marceline flew back out of her house, wearing a sunhat and long gloves.

Without so much as a word to the Ice King, she picked up her axe, and shot out into the sunlight.

Half an hour earlier, Ash skulked around the side of the tower at the centre of the Candy Kingdom. He crawled around the outside, like a spider, peeking into windows, searching for the Princess. The sound of creaking metal and grinding joints made Ash spin around, only to come face-to-face with one of the colossal Gumball Guardians.

"Halt!" It bellowed. "State your business, intruder to the royal castle!"

Ash thought fast. "Uuuuum, I'm not an intruder!" He insisted. He flicked his wand and, with a sparkle of rainbow-coloured light, turned into Princess Bubblegum. "I'm the Princess!" He finished, in the Princess' smooth, yet bossy voice.

The Gumball Guardian stared at him for a couple of seconds. "Error! Princess Bubblegum cannot walk on walls!" It stated.

Ash calmly floated to the nearest windowsill and rested his feet on it.

The Gumball Guardian twitched its head. "Identification complete. Have a nice day, Princess."

Ash stared at the Gumball Guardian in disbelief as it returned to the outskirts of the city and continued blowing enormous bubbles, along with the others. He really hadn't expected that to work.

Inside the castle, Bubblegum walked through one of the outer corridors in her lab coat and goggles, carefully making notes on a clipboard and humming one of Marceline's songs.

Suddenly, a window burst open and Marceline flew in, wearing a hoodie that kept the sun off her. She landed, closed the window and drew the curtain.

"Hey Marceline." Bubblegum smiled, as she lowered her hood.

The Princess walked over to hug her, but then stopped and frowned. She sighed and went back to walking down the corridor and humming.

"Bonnibel…?" Marceline called after her, confused.

"That's 'Princess Bubblegum' to you." Bubblegum said, without turning around. "Only Marceline gets to use my first name."

Marceline floated after her, her mouth hanging open in shock. A moment before she was about to talk again, Bubblegum continued.

"You're standing up straight, your expression is all wrong, and you're wearing perfume."

"It's called aftershave!" Marceline snapped.

"Sorry dude, but you'd be more convincing if, instead of a disguise, you just had a sign around your neck which said 'Marceline'." Bubblegum said, patronisingly.

She walked through a door into her lab, and the fake Marceline floated in after her.

"Ok fine. You got me. I'm Marceline's sister." She said.

"Marceline doesn't have a sister…" Bubblegum said, absent-mindedly, while she rooted through a drawer in one of the lab's cupboards.

"I'm Marceline from the future…?" The impostor tried, feebly.

Bubblegum's face lit up as she found what she was looking for. She produced a large flashlight from the drawer and shone it at the fake Marceline, revealing Ash's true features. Bubblegum turned the flashlight off and Ash stayed as he was.

"Ah man…" Ash moaned, as he realised what the flashlight had done.

"What do you want?" Bubblegum asked. "I'm kinda busy."

"I want you to leave my woman alone!" Ash snapped.

"Who now?"

"Marceline!"

Bubblegum stared for a while, until it dawned on her. "Oooh, you must be Ash." She said sadly.

"You've heard of me?" He said, sounding more smug that surprised.

Bubblegum drew a deep breath. "BANANA GAURDS!" She screamed, answering Ash's question.

Startled, Ash jumped back into the corridor and waved his wand, and the doorway to the lab slowly faded away, leaving a blank stretch of wall. Bubblegum ran over and punched at the wall, but it was solid.

"Princess Bubblegum!" Came the muffled voice of one of the banana guards, from the other side of the wall. "Is everything ok?"

Before Bubblegum could reply, she heard her own voice say, "Everything's fine! False alarm!"

"Oh… ok, take care!" Came the banana guard's reply, followed by the sound of their siren impersonation as they marched away.

"Wait! Come back!" Bubblegum cried. "That's not me!"

Bubblegum jumped back as she saw her own head phase through the wall.

"Oh, they can't hear you, you're gonna be in here for a while. Easily long enough for me to go break up with my girlfriend so she can get back to her awesome boyfriend, Ash!"

Bubblegum screamed and leapt at Ash, but he phased back and left her scratching at the wall. She stepped back and looked around the room. How stupid was Ash? Of all the rooms in the royal palace, he thought being sealed in her lab meant she was trapped? With the equipment she had, she could escape the room in two seconds, but she needed to be ready to help Marceline, once she saw through Ash's laughably transparent disguise. Marceline hadn't told her much about Ash's powers, just that he was a real jerk, and if she hadn't believed her before…

Bubblegum picked up a backpack from the floor and began filling it up with equipment.