To those waiting, here it is. I would like to point out that this all happens before "Sky Witch" and "Fire and Ice" I TRY to match the episodes, but I started WRITING this a year ago, and the whole story is around (Insert spoiler). I also have a side story planned with Marshall being turned and his survival after Simone (who is later in the story) leaves. Imagine a Walking Dead type of thing, but with Marshall. It'll be short, but enough to introduce the OC that is later in the story.
Alright I'm rambling. Here it is!

It was midnight and there floated Marshall infront of Fionna's window, with her staring at him. His body had locked up. The moons light was on Fionna perfectly. He blue eyes gleamed and her medium length hair was shining. Ever since she cut her hair, and tried to stop being Fionna the Human and tried to become Daisy the Normal, she had been trying to grow her hair back out. No matter the length Marshall loved it. He stared at her for some time before he realized he was just staring at her. "Oh! Hey Fionna… I was just strolling through the neighborhood and thought I'd come see you." Marshall closed his eyes and exhaled. "Honestly I just came by to talk. I-"
Fionna stopped him "Marshall… its fine. Just come in. It's cold."
Marshall swallowed. He floated in behind her. When he got in he noticed what she was wearing, just a tank top and pajamas. This was the first time he'd seen her like this. He still was wearing his black and red flannel and his torn jeans. When she turned and looked at him he looked away quickly and scoped out the room.
"So… um… Where's Cake?"
Fionna sighed "Ever since she had kittens she left more and stayed more at MoChro's house."
Marshall could see Fionna had been lonely without her around. "WELL…. I'm here now. So let's have fun!" Marshall flew at her and picked her up. He flew downstairs to the couch.
"Mar… Marshall it's midnight. Don't you think it's a little late to hang out?" Fionna rubbed her eyes. "Late? The day has just begun… Literally. So let's take advantage of this time." Marshall looked around. There was nothing for them to do. "Um… What can we do?"
Fionna patted the cushion next to her "We could Talk, it's been a while."
Marshall floated and sat next to her and listen as she went on about how adorable Cake and Monochromicorn's kids were, how she rode a flying squirrel, and how crazy the Lemongrabs had been recently. Marshall was interested, or he acted like he was. Then she finally stopped, and asked the dreaded question. "Marshall… why did you burn your arm?" She stared into Marshall's dark brown eyes. "I… ugh…. I was watching the world from my cave. I was remembering when I could walk in the sunlight. It was one thousand years ago, but it feels like yesterday, and I wanted to be out there. With everyone who was enjoying their life. I wanted to be adventuring with you. I'm so sick of being restrained by the vampire blood in my veins. Plus ever since you started dating Flame Boy, I have been more alone. I just wanted to be normal again…" Marshall's eyes trailed off.
Fionna noticed that he was in a bad place. She inched closer and pulled him into a headlock. "Look marshy. I know I've been distant, but that changes today. I'll come by more, I promise."
Marshall broke out her head lock and fixed his hair. "You don't have too if you-"Marshall stopped when Fionna wrapped her arms around him.
"I want to. So just shut up and let me be a friend." Fionna laughed and pulled away. Marshall's face started heating up. He put his hands of his face. Was he blushing? Did Fionna notice? So many thoughts were rushing through his head. His hands began to shake. "Hey… you okay?" Fionna put her hand on his. Marshall's whole body froze. 'Why am I so nervous? It's just a crush… isn't it?' He thought.
"Marshy? You in there?" Fionna snapped in his face.
"Yea! Yea! Just… bored."
Fionna looked around. "B-MO! Come here!" Within seconds a little blue computer walked in.
"Fi Fi! Do you want to play Video Games?!"Fionna looked at Marshall.
"I will never say no to Video Games Fionna. Just know you're going to lose. No stopping it."
Fionna laughed. "Alright. B-MO let's play… Marshall what do you want to play?" Marshall sat and thought. "Let's play Zombie Takeover" Marshall had always been a zombie fanatic.
"Fine… B-MO choose that so I can beat Marshall at it." Fionna said picking up the controller.
Marshall laughed "Beat me?! Be real I'm KING-"
Fionna jumped in "King Marshmallow ruler of the losers!" Fionna put her hand on her mouth "ooooohhhh! Whatcha going to do Marshmallow?"
Marshall smirked. "All this big talk from the girl who has YET to beat the loser. What does that make you? Ultra Uber loser?"
Fionna glared at Marshall. "Tonight I take that crown, and I will rub it in your face. So get ready to lose to a girl!"
The game began and the two sat and played for hours. Marshall kept a close score to Fionna, he did not want to beat her tonight. Near the end he pulled back and let Fionna take the win. She jumped up and screamed. "OH! Where's that good stuff you were talking now?!"
Marshall smiled "Well… I guess you win… for once."
Fionna danced around "I beat King Marshmallow! How's it feel to lose Marshall Lee the Loser?"
Marshall laughed, she was so adorable. "It feels… terrible, but always next time."
Fionna laughed "That's what losers say!" Her being this happy over a game was the cutest thing he ever saw. 'Now I know why I like her.' She was so happy, and her happiness brought Marshall his own happiness. Finally she calmed down, and looked at Marshall. "I'm sorry…" She began to blush.
"It's fine Fi. You earned it."
She walked back to the couch and sat next to Marshall. "So you want to watch a movie?"
"Sure. What movie?"
Fionna jumped up "The amazing Heat Signature!"
Marshall mentally sighed. This would be the eighth time he'd seen it, but for Fionna it was worth one more time. "YES! Let's watch it."
She ran over to the drawer full of old pre-war movies. After some searching she pulled one out and ran to B-MO. She put the tape in and jumped back to being next to Marshall. As the movie played she would jump and grab Marshall. This was happiness for him. He might not have her as his, but something with her was better than a life without her. The movie was finally coming to a close and Fionna had stopped jumping. Instead she just rested her head on him. He leaned down and looked at her. She was out cold. Her mouth hung open and she had begun to snore. Marshall's dad use to tell him that you don't know you love a woman until you see her sleep and eat. He also said every great man's fall came from a woman. Marshall was only five when his dad said all these things. Now seeing Fionna, he knew he did not like her. It was more than that. Even though he saw her in a very embarrassing manner he still thought she was the most beautiful creature to ever exist. That was love to Marshall. That was what he was feeling towards Fionna. He leaned his head back against the couch and decided that instead of carrying her to bed, he would just enjoy the moment. His eyes slowly began to close. He rubbed her hair and whispered "Goodnight my love." Within seconds he was also asleep. The last thought that ran through his mind was that he had made a good choice coming over today, but the day had just began for Marshall. One that would change his and Fionna's life.

ALSO tell me if you like me Italicizing their dialogue. I don't know if it's easier with it or not.
Alright well it's 4:30am and I have class in three and a half hours. I hope you guys enjoy this cause it keeps me up.
This the Broken (Now known as The Vampiric King) signing off. See you space cowboy.