Sorry for the brevity of this chapter, but I wanted a little simple fluff. It will get more interesting in the future.

Disclaimer: Still don't own Adventure Time, I'm so sad xP

Enjoy, R&R!

Marceline flew into Bubblegum's room and closed the door with her foot, easing the princess onto the bed gently. She flew back to the door and locked it, floating to the dressers and taking articles of clothing out of the drawers. She went back to the bed, laughing at Bubblegum's sprawling form.
"You've gotta help me out here, Prubbs. Sit up."
The princess shook her head into the pillow, and with an amused sigh, Marceline sat beside her on the bed. She pulled the princess up into a light embrace, slipping a pair of pink flannel pajama pants up her legs.
"Arms up." Bubblegum raised her arms, and Marceline shimmied the dress slip up and off of her, swallowing hard when she unclasped her bra. It fell to the floor in a heap with the slip, and she moved to work the button-up top onto her shoulders when she was stopped by a moan.
"Nooo…not that one…" Marceline cocked an eyebrow.
"What?"
"That one…" Bubblegum pointed to the nightstand beside her bed, and Marceline opened it to find the black rock shirt she had gifted her many years before. Flattered, she smiled widely, and moved to pull it over the princess's head instead of the flannel.
"I thought you weren't serious when you said you wore this thing…" A blush stained the vampire's cheeks cobalt, and her voice wavered a bit with emotion. Bubblegum yawned and fell out of Marceline's arms onto the bed, slithering under the covers lazily. Her breathing evened out, so Marceline shrugged, turning to fly out the window.
"You can't leave, Marce…"
"Sure I can. I've got at least two hours before sunrise." Marceline scanned the sky, noting how the stars were slowly beginning to fade into their slumber.
"No…I mean, you've got my crown…" Marceline's hand shot up to her head, and she laughed.
"The first kingdom I've ever won without having to kill a vampire. Fantastic."
"Get back here and give that back…" Bubblegum's voice grew slightly stronger than the tired whisper from before, and Marceline figured she'd better hurry up so the princess could sleep. She floated to Bubblegum's bedside, depositing the crown onto her nightstand. She smiled down at the princess and turned to take her leave when she was stopped suddenly by a hand on her wrist.
"Bonnie?..." The princess's head was buried in her pillow, her free arm holding it tightly. She peeked out from under the pink mass, smiling.
"Stay with me tonight, Marce?" The invitation was quiet, and Marceline felt her blush return, accompanied by a small smirk.
"I didn't bring any PJ's, Peebs. Wasn't expecting a slumber party, ya know?" Marceline chuckled, rubbing the back of her head. Princess Bubblegum pointed to the discarded flannel nightshirt.
"Great, but jeans aren't exactly fit for sleeping…"
Bubblegum pointed to the shirt more insistently, and added "It's long enough…" Marceline chewed on her lower lip nervously, going to the window and pulling the blinds closed. She took off her sweater and threw her bra with it to the corner of the room with the Princess's slip. She buttoned up the flannel and slid her shoes off with her socks and pants, walking towards a reading chair.
"Stop fooling around, Marceline. Come to bed quickly, I'm really tired…" Bubblegum raised the covers beside her and patted the bed, looking at Marceline expectantly.
"Alright, alright. I'm coming." Marceline crawled into bed, smiling shyly at the princess, who lay facing her.
"Ah, we forgot about Science…is it really ok for science to stay in the lab all night?" Marceline asked, trying to break the awkward silence. Bubblegum nodded.
"Science has a cage in the lab. It is perfectly fine." Bubblegum's response was curt; was she nervous, too? Marceline shook her head. Of course not, she had no reason to feel nervous. She was probably just tired, and she was sick, after all. Sick…
Marceline's hand shot up to the princess's forehead, and noticed for the first time her flushed cheeks and shallow breathing.
"Bonnie, you're worse…"
"Nonsense!" Bubblegum pulled the vampire's hand to her forehead tighter. "This feels good, though…I may have a light fever, Marceline, but I will be fine by morning."
The hotness against her palm alarmed Marceline, and she scooted closer to the princess.
"C-come here…"
Bubblegum slid to Marceline's side, sighing happily when she felt the soothing coolness of the vampire's body against her own.
"My own personal cold pack…I will be over this fever in no time with you, Marcy. Thank you…" She pressed herself to the vampire. Marceline looked down at the princess in her arms happily.
"Go to sleep, Princess. Sweet dreams." Bubblegum nuzzled into the vampire's neck, and Marceline kissed her forehead, hugging her tighter.
"Night, Marcy."

Marceline awoke the next morning feeling more rested than she had in years. She yawned deeply, looking down quizzically when she found herself unable to raise her arms in a stretch. The sight made her smile:
Princess Bubblegum lay atop the vampire's left arm, hair splayed over the pillow in soft cascades. Her face was peaceful and her breathing was soft. Marceline thought to herself that the princess looked like an angel. An angel with a very deep blush…
Marceline touched her hand to her forehead; the princess was burning hot. She sighed inwardly and decided to get some medicine for her friend. Trying to get up, she felt the arm around her waist tighten, and she sighed.
"Princess, you need some fever reducer. I need to go down to the lab, I'll be right back…"
"My cold paaaack…" Bubblegum pouted visibly.
"Since when were you so whiny? And besides, I'm more like a lukewarm-pack now, babe." The princess moaned, pulling away from the vampire and turning the other way.
"Fine, fine…Science knows where everything is in the lab…" Marceline smiled. She climbed out of the bed and pulled on her pants, and, too lazy to dress, slipped on her shoes without socks and floated to the door still in the flannel.
"Marcy?" Bubblegum called.
"Yeah?"
"Nice panties…" With that, the blushing Marceline floated out the door while a giggling Bubblegum burrowed under the covers.