AN: Got my inspiration on the song Warzone by The Wanted. Lyrics aren't mine. Adventure Time isn't mine.
I can't believe I had to see, the girl of my dreams cheating on me.
It was a peaceful evening. Finn was lying on his back, facing the woody ceiling of the treehouse he lives in with his bro, Jake.
"Jaaaaake! I'm bored!" Finn whined to Jake who was concentrating on a video game on Bee Mo.
"Whatever, man. I'm busy beating your high score here." Jake said, eyes still glued on to Bee Mo's screen.
Finn puts his two arms behind his head. "What do you think I should do?"
"You have a girlfriend. Why don't you give her a surprise visit or something."
Finn immmediately stood up and straps on his green backpack. "That's a great idea! Thanks man." He strolled out of the door, unsure if Jake said goodluck or not.
Finn stood before the door of his girlfriend's house. It was already late at night. He knew his girlfriend wouldn't be too upset since she's a vampire. Basically they're nocturnal; they sleep during the day and come out at night. He knocked on the door. No answer. He knocked on it the second time. Still none. Then he heard his girlfriend's voice but not clearly enough to make out the words. He decided to go in anyway since he knew she wouldn't mind much.
"Marceline?" he whispered softly as he entered the dark living room. Strange he thought. She always has the living room lit up when she's home.
He goes in the kitchen but finds no one. He then heard a slight thump above him. She must be in her room he thought, feeling relieved. He slowly climbed up the ladder, keeping quiet with every step he took. As he got closer to the door of her room, he heard soft moans and scuttling behind that door. His throat tightened as his mind came to some conclusion on what was happening. His heart was pounding uncontrallably. He gently pushed the door away and took a peek. What he saw made his heart break terribly. Marceline was lying down on her bed, naked, with her legs spread out wide. On top was a pink haired princess fingering the vampire and sucking on her breasts.
"Bubblegum," she breathed and moaned her name. Finn's eyes were welling up with tears. He pushed the door with great force just to let the twosome know he was present. They stopped and stared at Finn with alarmed expressions.
Finn didn't remember what happened next. He only knew he went down the ladder and ran out of the house. He didn't remember Marceline apologizing. He didn't remember the trip back to his treehouse. He only remembered the pain in his hands and feet the next morning. They were bloodied and scarred. Just like his heart.
3 weeks later
The pain you caused has left me dead inside. I'm gonna make sure you regret that night.
"Finn, you wanna slay some orcs today?" Jake asked, hoping Finn would agree. Finn sighed and rolled on to his side as he wrapped the covers of his bed around his trembling body. Jake took note of his trembling figure and placed his palm on his forehead.
"Finn, you're burning up with a fever!" Jake exclaimed as he hurriedly ran to the kitchen to get a cold compress.
Finn first felt hurt and sadness at the first two weeks. Now, those feelings were replaced with something else. He felt vengeful and anger heating up his body. He slowly sat up from his bed, oblivious from the fact he was trembling. He will get revenge and make them pay.
Later that night
I feel you close, I feel you breathe and now it's like you're here. You're haunting me. You're out of line. You're out of sight.
Finn was having a hard time trying to get some sleep. The cold compress on his forehead was getting warmer by each passing minute. He looks out to the window, seeing a beautiful full moon in the night sky. He continues staring at it, hoping to eventually doze off to sleep. He slowly felt his eyelids drooping and closes them, shutting him off from sight. A moment passed when he felt someone close. He tried to ignore it for maybe it was plain paranoia. Suddenly he felt a cool breath against his neck and he immediately snapped his eyes open. He looked around the room but found nothing.
Still, he had a nagging idea that Marceline was just invisible once again, out of sight from his eyes, out of line from his privacy and a creepy notion to haunt him for forgiveness.
Several months later
Everywhere I walk I see your face. Try to erase a memory with a flame and hope I never see you again. Standing here in this burning room.
Jake tried to be a good friend. He set Finn up with a couple of princessess on dates just to get his mind off from the hurtful breakup. One princess from another, Finn still didn't feel okay. Finn finally told Jake to stop setting him up anymore dates.
"Dude, just one last date and I'll stop!" Jake protested. Finn sighed and hunched his back.
"Well...okay. Just this last time." After Finn said it Jake excitedly told him about the princess he is going to meet.
"She's hot and flamin' and very passionate too," Jake rambled on as he cleaned up the dishes on the table.
"We're going to the Fire Kingdom by the way."
They walked all the way to the Fire Kingdom. Everywhere Finn looked he was reminded off Marceline from the tiniest details. He shook it off and arrived at the entrance of the fiery kingdom.
"Flambo is going to cast the Fire Shield on us before going in or else we'll get burned to ashes," Jake informed Finn as a tiny Flame-like humanoid approached them and chanted something.
"No problem Jake!" the tiny flame dude said.
They arrived at the palace on Jake's back with Flambo tagging along. Finn didn't pay much attention as his imagination slowly popped in. He saw the Fire King talking to Jake, Jake singing a song and pushing him towards the king holding a Jake-made box with a koala in it that kept saying 'Eucalyptus'.
He finally saw the Fire Princess in a lamp beside the king's throne. She was stunning. The sight of her made Finn's mind go blank. He saw the king letting her go free from the lamp as she hugged him tight.
"My prince!" she said as she continued hugging him with a warm smile. He smiled back at the flaming princess before him. He hoped to never see the vampire again if he stayed in this burning room with the burning princess beside him.
A Year later
So I know I just gotta let it go. I shoulda' known. I gotta learn to say goodbye now. I throw my armour down and leave the battleground for the final time now I know I'm running from a warzone.
A year has passed and Finn's heart is partially healed. He didn't mind. He knew if he stayed close to his Fire Princess he would be fully healed in no time with ease. He finally accepted the goodbye from his past relationship with Marceline. He threw his old armor down (Marceline) and had put on a new one (Fire Princess). He left the old battleground (his old relationship and memories with Marceline) and ran off from the old warzone (conflicts and pain) into a state of tranquility and peace in the arms of his new love.