Hey! This is a little one-shot Fiolee story I'm doing. (: It's roughly based on Marcaline's Closet using my favorite paring Marshall Lee and Fionna! Also, in this Fic Fionna will be eighteen for all intensive purposes. Rated M for language and adult themes.

I do not own Adventure Time.

Enjoy!

The young adventuress quietly walked closer to the mouth of the cave humming softly to herself. Tendrils of loose hair whipped freely from her bunny hat and into the faint breeze. With a balloon tucked into her under arm and an excited smile dressed on her face, she ventured further into the heart of the dark cave.

As she approached the vampire kings home, she curiously glanced at the note taped on his door.

Fi,
I had to run out but I'll be back. We'll start our Jam Session as soon as I return home. Don't go in my house.
-Marshall Lee

Fionna sighed suddenly wishing Cake had come along to her annual Jam Session with Marshall Lee. The blond adventuress curiously glanced at the slightly ajar door but thought better of it. Don't go in my house, flittered around in her head.

When Marshall's zombie poodle, Schwable, nudged her nose into her heel, asking for affection Fionna happily obliged. She reached down and gently pat the undead creatures fur a few times before Schwable happily scampered away.

She occupied herself with gently singing a melody that carried throughout the cave and looking around, noticing things she hadn't before. But soon she grew bored again and her eyes wander to the door.

Ignoring Marshall's rule of not being in his house, Fionna found herself in his lair- as he likes to call it- shifting through his things.

Honestly she'd be lying if she said she wasn't attracted to the dangerous vampire. She spent all of her time with PG which often left her bored and yearning for Marshall. She spent so much of her time with Princes, sometimes she needed a King.

Fionna heats up at a memory of when Marshall came over to play video games while Cake was away.

"Marshi," she had moaned lightly as the Vampire King latched onto a sensitive spot on her neck.

"Take it back, Fi."

The blond adventuress firmly stated that she'd beaten him and that she hadn't used cheats or shortcuts.

"N-no!" she cried out clinging to Marshall's shoulders. The overwhelming attack on her neck an all new sensation ever so innocent eighteen year old.

That night she laid panting and sweaty in her bed as she pleasured herself to thoughts of him.

Fionna continued her snooping about Marshall's home. Her fingers danced over his bass, she traced the soft silk of his bed, she played with his keyboard momentarily only to grow bored again.

Where was he?

As if on command, the opening and closing of the door rung out into Marshall's home shattering the young humans thoughts. "Shit," she cursed quietly, quickly scampering into his closet so she wouldn't get caught.

"Fionna?" Marshall called out into his home.

Through the shutters in the Vampires closet, Fionna watched as Marshall floated into his room.

"Well, I guess I'll just have to work on my own stuff then," he huffed.
He began shifting through the pages of a large notebook until he found whatever he was looking for. "Take one- Blessed night.

Fear struck, blood lust

Kill the lights, I don't like the bright

Watch myself burn away

In the sun it's sure to stay

Harbor me please keep me safe...

Blessed night!

Guide me to all that's right

Blessed ni-"

"Oh glob, this is so wrong," the human whispered desperately to herself. The vampire continued playing. His words became deeper and more meaningful as Fionna tried to tune him out.

All of a sudden the Vampire King stoped, sighed and dragged his body toward the bathroom.

"I need to scope it out," the adventuress decided and slithered her body about his room.

She stopped at Marshall's bathroom door and cautiously poked her head in. And there stood Marshall, in all his glory, sporting only his boxers. Fionna let out an involuntary gasp and the vampire whipped around.

"How long?" he asked surprisingly calm.

"The whole time. Marshy I'm-" she's cut off by the vampire grabbing her petite body and hauling her to his bed.

He set her down gently and smirked at her. "What did I say Fi, Don't go in my house."

"I know- oh oh! Marshall!"

The vampire began his assault on the adventuress by sucking on her pulse point. She threw her head back exposing more of her neck to him as he started placing cool kisses on her body.

"Didn't anyone ever teach you about manners?" he hissed ghosting his lips over hers then fiercely claiming her mouth as his own.

"I-I'm sorry," Fionna chocked out between her whimpers. "Marshy.."
Her nickname for him sent a twitch to his cock as if the sight of the adventuress herself didn't make him hard. He gently scraped his sharp teeth across her soft skin as if not to break it. "Say it again Fi," he demanded.

"Marshy," she whimpered lightly. "Please don't stop."

The vampire sat the blond up and tugged off her shirt, revealing her cherry red bra and supple breasts. He took his time to suck the red from her bra, making it dull then quickly disposing of it.

Fionna's breast were exposed to the air and her nipples perked up. Marshall dragged his tongue up her body then traced her ear. "I'm gonna make you come so hard that all you will be able to remember is my name, Baby girl," he whispered to her. She moaned in response.

He took that moment to kiss her. His lips moved feverishly against hers. He traced his forked tongue along the bottom of her lip asking for entrance. She happily obliged opening her mouth to him. After thoroughly exploring her mouth and wrestling her tongue in a fight for dominance he relented and let the human break for air.

"Fuck," she huffed looking quite a mess with her hair hanging loose and warm, flushed cheeks.

Oh, but he wasn't done.

He began sucking on her breast right as she calmed herself down enticing a sharp cry from the young female. She was fisting his hair now. Her breathing gone ragged.

She was close, he could tell, so with one swift motion he stripped the girl of her skirt, very pleased to learn she wasn't wearing underwear.

"Not fair," she panted out.

The vampire thrust a finger inside her and stopped his assault on her breasts. By now the adventuress had slumped her body against his, her legs were wrapped around his waist in order to keep herself on his lap. Her eyes were halfway lidded over as her plunged his finger inside her over and over again.

Suddenly, she screwed her eyes shut and her body tensed in his lap. "Marshy!" She screamed clinging onto his shoulders riding out the high of her orgasm.

Marshall Lee smirked at his work but his member throbbed painfully reminding him of the release he needed.

He gently laid Fionna down on her back and took off his boxers. He had himself hovering over the petite girl, positioned at her center. "Is this okay?" he whispered gently into her ear. He felt her shiver.

"Glob, yes. Marshall just fuck me," she whined.

He didn't need to be told twice.

He thruster into her dripping wet center and they both moaned together. "Fuck Fi," he gritted out. "You're so tight."

A soft "Marshy," was all he got in return.

They found a rhythm. She matched his rough thrusts with equal fever. They're bodies smacked together in a hot clusterfuck of passion, lust, and love.

"Harder," Fionna begged. "Please Marshall."

Marshall picked up the place and slammed into her tiny frame harder. He wasn't gonna last much longer. He reached between their legs and teased her sensitive bundle of nerves.

"Shit!" she cried out clamping her walls around his member. After a few more short, shallow thrusts he followed, emptied himself into her center then flopped down beside her.

He pulled the petite girl into his side then threw the blanket over their naked bodies.

Almost taken by sleep, the beautiful blond adventuress, with her head on the Vampire Kings chest, murmured a final, "G'night Marshy."

Marshall placed a kiss to her temple. "Goodnight baby girl. I love you."