I always have an idea of incorporating a music into Adventure time fanfiction, since there is so much music on the show in the first place. Then an even better idea hit me, instead of putting a lyric in the story, why not just built the story upon the lyrics. Some lyrics will be changed to fit the story. Well, here we go. Wish me luck.

Chapter one: Betrayal

Disclaimer: All materials are owned by its owner, I own nothing. I.E. Adventure time is a property of Cartoon Network, and Betrayal is a song by Lita Ford.

…

"Dad! Stop!"

Finn Mertens tried to pull as hard as he can, pulled hard as if his life depends on it. His left-hand held on to some branch of a cosmic shard that was cut earlier. His right-hand gripped hard into the other piece that starts to fly off, carrying a handful number of the universe worst criminals on board. Unfortunately, his father was one of them.

"Martin, I won't let you escape", Shouted the boy. Things didn't go the same way he expected. He always wants to meet his biological dad, always. To find out where he came from, to find out about other humans, it's always his wish. When he heard from Billy that his dad still alive, he was overjoyed, follow by paranoia. He always afraid that things will not turn out how he wants it to be. He always afraid that he would be wrong, or he would destroy everything he had built so far as he did with Flame Princess. He even lied to himself that his dad might be a warden when Prismo told him what the Citadel was.

Now look what happens, a prison break instigated by the Lich. The guardians were all down, those monsters got free, and his scumbag of a dad manipulated him and ditched him at the first moment possible. Martin didn't even recognize him as his son, not when Finn could not provide him with any help anyway.

Murphy's law, bitches.

Finn pulled as hard as he could. His arms started to give away to weariness. How could his dad do this to him, is he really his dad at all?

"Hey, hey. You're a void caster, right? We gotta put some …" Martin hit his conversation partner leg, apparently, it makes him looks and sounds friendly. "… Gas in this bucky".

The drag got stronger. It's too much of his grip strength. Even though, he tried to hold on the best he can, even it become painful. He wailed in pain, sweats, and tears mixed and flowed all over his face. He would fail, again. "Finn, let go. He's not worth it" His adoptive brother cried, trying to knock some sense back into him. 'No', Finn said to himself, internally. He had come too far, he had sacrificed too much. He won't take no for an answer, not now.

"WHHHHAAAAAAAAAAAAAAAAAAHHH!" Finn screamed in a mixed emotion of rage and sorrow. The cursed bladed reacted to its master deepest wishes, taken over his entire right arm and grant him a tremendous strength. 'If I had to lose my favorite arm to win, then so be it' He reconciled.

It's working. He felt that his hold on the shard getting stronger. It's only the matter of time before he pulls it back to the Citadel. Then, he would to punch his bastard of a dad for all the pain he had caused him over the years. Revenge is a dish best served cold but an extra dessert for today betrayal is also an interesting dish he wants to give his "Father". IN HIS FACE.

"Pedal to the metal" Finn heard his dad shout in a jokingly manner. 'What!' He screamed internally as the hold in the space that the void caster created getting larger. "Whhhhaaaaaaahhh" He cried, this pull was too much, he's not going make it.

SNAP!

Time slowed down to a crawl for Finn Mertens. He is shocked to see that his cursed arm starts to tear itself apart from his body. Bundle by bundle it falls off, giving him an excruciating pain that he had never imagined before.

AND HE HAD KISSED A LIVING FIRE AND ONCE JUMPED HEAD FIRST IN A VOLCANO.

He failed, Martin got away. His eyes start to get burly, his mind becomes blank. All the pain, physically and mentally, is too much for a 15 years old mind to handle. He fell into the Citadel's water like a rock.

Now, he had lost everything.

His girlfriend, whom he betrayed and messed up any change for getting together again after the Red Throne incident.

His friend, Prismo. Well, he is more like Jake's friend but its close enough.

His father, that sly manipulative bastard.

His right arm.

HIS RIGHT ARM!

And it seemed he will lose his life too, here, in the Citadel.

With a blank stare, he looked at the blind eternity in from of him. 'What a pathetic excuse of a hero I turned out to be' he thought. Everything was dark and murky, but he still saw some light. It's come from something that resembles a face. A no emotion face of a fallen Citadel's guardian.

'Oh no, no, no, no!, no!, no!, no!'.

And then everything went white.

…

"Through the lake, a boy drowned sadly.

Something is broken in his chest.

He dared to trust his father.

Alas, no better than the rest.

Down my path, he sunk broken.

Something opens up my cell.

I longed to stop his bleeding heart.

And so, I call him to where I dwelled.

Those you trust will hurt you badly.

Something now I'm sure you see.

So, drown your tears in me, my dear.

As you drown, my dear, in me."

Disclaimer 2: If you thought that "Hey, you nicked that poem from Brutal Legend! (and change it to fit the narrative too, well done)", then yes, an extra point for you sir/madam. By the way, Brutal Legend is owned by Double Fine studio (the make own's it right? Really, I don't know how its work.), and is published by EA (Still salty there is no sequel here)

…

Finn felt like his body was on fire. 'This must be what dying feels like'. A shot by the Citadel guardian laser must have disintegrated him down to dust. All that he felt must be a way for his primitive human conscious trying to process what happened.

And then everything went cold. He felt, SAD. He could still see nothing, but he felt save, somehow. This cold embrace was lovely, it took all his pain away. All his negative momories resurfaced, his mental vault had been broken, all those bad memories rushed forth. Yet, he felt nothing, nothing at all. He was at peace, at last.

"Poor child" He heard a word from the most beautiful voice he had ever encounter in his life, and in all his past life too. "You were destined to be great, you sacrificed so much with your immortal soul" The voice continued. "You bring life to a planet as a catalyst comet, you spend your time on it over and over and over. Building yourself a cage that you don't even know how to get out" The voice shaken, sadness filled to the brim in its tone. "Let the music set you free"

Everything faded to black

…

Finn woke up with a massive headache, he still felt like his body is still on fire. However, it's cleared that he was not in the Citadel anymore. 'What happened', he asked himself while looking around. His vision was still blurry, but he could make out some of the shape and color that is mainly white and pink. 'Suppose the afterlife is not that bad. Maybe Dead do me a favor and try to make me feels at home before he tried to have my flesh, that is' He wanted to punch himself for having that thought, but his arms were too weak to even lift themselves up.

"He's awake" He heard a familiar voice of a certain princess he has a crush on long ago. A love that is never and will never be returned to him. Finn turned toward the voice and sees a certain pink and white figure that he assumed was Princess Bubblegum in a lab coat. 'Dead really pays a lot of his attention to detail, bravo' He thought. "Heaven?" He asked jokingly which received a chuckled as a response. "Angel?" The chucked response is even louder this time.

"Silly Finn. You are in the hospital in my Candy Kingdom" the pink figure replied, "You have been in a coma for weeks". 'Oh, so that what it is …. WAIT WHAT!' a mental double takes from the young hero.

"Aaaaaaaaaaaahhh" Finn screeched. "DAD! NO!" He jumped up on his hospital bed, causing a shocked reaction to the princess and the hospital staff in the room. They rushed in and tied him down immediately. "I'm sorry Finn, but you have to rest. From what Jake had told me, I believe he's not worth it…" Said the princess, petting him in the head "He doesn't deserve you".

Even though the princess wanted to help the young hero and provide him a comfort, she knew that only time can cure this sort of thing. Finn could do nothing but accept the truth and move on with his life, least he would continue to hurt himself forever. "You need to rest, I will call Jake to come to take care of you" She said, placing her hands on his "All of us are worried about you, Finn. Jake, Marceline, Lady Rainicorn, BMO, Me, heck even Ice King drop by and cried the one time" She kisseed him in his forehead "Have a nice rest, my hero". Then she walked away, leaving Finn to lie-down and rest, with a restraint of course.

…

Another week went by. Finn was out of the hospital and moved back to his tree house. He had a recurring nightmare, an unusual one that constantly told him "Let the music set you free" both in his sleep and when he was awake. Furthermore, the thought of losing his dad still set in his mind while the effect of a cold embrace he felt when he thought he had died down. His life was back to painful and miserable once again.

"Bro! You're doing it again" said Jake the dog, worried for his brother. "Come on, cheers up, man" He hugged his brother with his elongated and flexible arm. "You know what, let's go to Marceline place and have a jamming session this evening. That's will surely cheer you up"

"Jamming session, eh. Maybe that's what I need" The young boy said it out loud. Maybe that's what the voice in his head means, played some music and forgot about the bad stuff. Heck, it's better than him sitting on the coach and wallowing in despair anyway.

"Who are you talking to bro?" asked the dog. "Nothing. Did I just say that out loud?" replied the human, he tried to make a cover-up smile. Jake was sure that there is something wrong his adoptive brother. After they got back from the Citadel, Finn had changed. He was so downed and sad all the time. Trying to think positively, as he always does, he ignored it and hoped the jamming session with the vampire queen would solve everything.

…

In the evening, both Finn and Jake traveled to Marceline's place. The vampire queen opens her door happily and greets them. She flew in and proceeds to hug Finn. A hug so tight it might break some of his bone, but that's the matter for another day. "Dude, I thought you are a goner" She said half-jokingly. "Me too, Marcy. Me too" replied the hero. "Come on in, let's have some fun. I'm gonna make your trouble goes away. With the power of music" She winked at him, of which he responded with a nervous chuckle.

…

Turn Out It's Not

A jam went poorly, as Finn constantly dosed off during the song. They tried to call him out, make him snap out of it over, and over until the vampire queen had enough. "Enough! Finn, What's the hell?" She hissed at him. Apparently, Marceline took this jamming session a bit too seriously. "Why can't you just, you know, go back to normal!" She grunted, which irritate Jake. "Dude, that was way over the line, Man" replied the dog. Jake's always protective of his brother, even though Finn is the reason why it went poorly. The tension could not have been higher.

"Marcy," Said the human, breaking the tension in the room. "Can I borrow your guitar?" He uttered a statement that shock both of his companion. He didn't know what he's doing either, but he felt that it is right, somehow. "But you don't know how to play guitar" replied the vampire queen. 'Or any musical instrument what so ever bar the simple shaking one' she kept the last part to herself, not wanting the boy to get hurt by her word. "Please?" asked the human. No, he begged her for it. An action she could not bring herself to refuse.

"Here you are" She handed her guitar to the boy. It's an old Gibson Flying V model that she had stored in her attic for a long time. She chose that one because it's the latest one that she had tuned, and that's is about years ago. "Show me what you got"

What happens next made both Marceline and Jake drop their jaws to the floor. As soon as Finn get a hand on the guitar, he started fiddling with its strings and tuning it by what he heard alone. He then grabbed the guitar, took a deep breath, and proceeded to play one of the sickest guitar-solo the vampire queen has ever heard in a long time. 'What's going on here? Since when he can play guitar, or any musical instrument like that?' Thought the queen, she didn't speak it out loud as her pride as a musician hold her back. Too bad for her, the dog was not as subtle "Cool bro! When did you learn to do that?" Jake moved his arm over his brother's shoulder and hugged the human head. "You played even better than Marceline! hehehehe" a comment that irritated the vampire queen to no end.

"I don't know, bro. It's just happened" Replied the boy "It felt, hm, natural?" He then proceeded to do another short riff. "Actually, I want to show you something. It's stuck in my head for a while now"

"Let the music set you free"

'That's voice again' He thought. 'Maybe this is what I have to do'. "I call this song, Betrayal. It's dedicated to my jerk of a dad" He said artistically before playing a song.

…

"Crawling by the sea of black tears. Give your soul to me.

I'm done with being betrayed. I don't want your sympathy.

I'm the maker of this world, you know.

You're are so predictable now give me your soul.

1 2 3 4"

As Finn dug deep into his song, something was changing inside him. Things that had not gone unnoticed by both of his friends. However, his song was so captivating that both cannot do anything or think of anything but sway to the music he played.

"Betrayal running through my veins.

I'm in the underworld.

The fear in your eyes, I'm the lump in your throat.

The shiver down your spine, you're so devoted.

Come join my army of betrayed and obscene.

I'll give you nothing because that all you need."

Finn continued to play the song that came up in his head, automatically. It seemed that he had no control in his hand or mouth and throat at all. Everything just happens. He could not even hold back the tears in his eyes as it comes out.

"Betrayal running through my veins.

I'm in the underworld.

The BRUTAL LEGEND, BRUTAL …."

And then it came, the sickest solo he ever played or heard before. Finn could still not believe that he is the one who played it. His tears streamed out as the solo go on, so much that it snapped his audiences out of the trances.

"The BRUTAL LEGEND, BRUTAL PAIN!"

The song was finished but the tears didn't stop. His tears flooded the living room until his friends snap him out of it. "Finn are you okay!" Screamed the worried vampire queen. "Oh, it's okay now Marceline. Sorry about crying all over your home" replied the human.

"No, you dingdong. Look at your tears. It's black!"

…

/ A week earlier

As she went back to her laboratory, Princess Bubblegum peeled off the sealed layer of her lips that she had prepared beforehand. She started analyzing her sample with the help of her lab rat, Science, right away. Something was wrong with Finn, the reading from her equipment showed her so, his cells had changes in some way. Some way that she doesn't understand or is ever been recorded before.

It was something that reeks of power that even her scientific mind didn't understand.

And that frightened her to her candy elemental core

…

Well, that's chapter 1, everyone. Can't believe I wrote it in one sitting.

Here's what I planned to do with this series

1) It will have a plot of its own while following the canon storyline. I will use the episode that will fit the song I had been thought about other than the other way around. But I will keep things in a chronological order.

2) I plan to complete this series in about less than 10 chapters since that about the number of the song I have thought and plan to build a narrative upon. For example,

Finn sings "Darkness Within" by Machine Head.

Pheobe (Flame Princess) sings either "Set Fire to the Rain" or "Rolling in the Deep" by Adele

Finn sings "You Give Love a Bad Name" by Bon Jovi

Simon/Ice King sings "Diary of a Madman" by Ozzy Osbourne

Someone sings "I Will Survive" by Gloria Gaynor but I still didn't work out the setting for it yet.

Someone sings "Smooth" by Santana/ feat. Rob Thomas but I need to think how to put it in the story.

Etc.

3) If the series went well, I might do a sequel. Feel free to request a song. Think of it as a challenge for me to write. I might ignore it due to my limited imagination though.

Cheers. See you in a few weeks time.