Disclaimer: I do not own Adventure Time or Gravity Falls. Contents belong to Pen Ward and Alex Hirsch. I do not own the song My Life is a Party by italobrothers.

ADVENTURE TIME: THE RETURN OF BILL

Ten weeks after the events of the Red Throne, Finn the Human decides to go on a dungeon crawl. He entered the dungeons entrance and looked around. Ancient hieroglyphs covered the walls, skeletons were everywhere, and the air smelled of death. "Ugh, well, dungeon crawl, down we go." he said in a half hearted tone and drew his grass sword and went down the dark hallway.

Earlier that morning…

Finn woke up feeling groggy. His body was fine and fully rested, but his mind was filled with depression and pain. Last night Flame Princess called, wondering how he was. He hadn't talked to her since the incident of the Red Throne, he felt like he had failed her. She came to him for help to retake the throne from her evil father, the Flame King. And to stop the Flame Lord, Don John from marrying her. When the moment came for him to prove himself, he made a absolut fool out of himself. In the end, Cinnamon Bun saved the day, he was the true hero that day, not him. When he got dressed, he went downstairs to see his best bro, Jake making his famous bacon pancakes and singing.

"Hey Finn, how did you sleep?" Jake asked

"Eh, not that much." replied Finn

"Aw, you still hung up about Flame Princess calling last night?" said Jake

"Um hm." moaned Finn flopping onto the couch. Jake turned off the stove top and stretched over to Finn and placed his paw on his shoulder. "Come on bro, you know I hate to see you like this. When your all bumed, I'm all bumed too." said Jake trying to comfort his brother. "Sigh, I know man, and I'm sorry. But I just can't get her out of my head, it's like I was on top of the world when she came to me, to me Jake for help. And when the time came to prove myself to her, I donked it all up." he said and buried his face into his hands. "Aw, I'm sorry buddy, is there anything that I can do to make you feel better." said Jake. Finn just shrugged and sighed, "I don't know what you can do to fill this emptiness in my chest man." said Finn. Jake pondered for a good two minutes until a idea popped in his head, "Hey, I know what will make you feel better, let's go visit Flambo's brother." he said. Finn was confused by Jake's idea. "How will going to see Flambo's brother make me feel better?" said Finn, "Psh, dude, don't you remember the last time we saw him, he gave us a map to a dungeon and we found the dungeon train, that made you feel better." said Jake, "Oh yeah, hey, we could go to the dungeon train!" said Finn, "No, any place but there, you almost stayed there forever, remember." said Jake, "Oh yeah, right, nevermind." said Finn, "Maybe he might have another map to another dungeon, maybe almost like the dungeon train, but without that bad mojo that makes you stay forever." said Jake. "Yeah, whoo, man I feel better already, let's go." said Finn doing a flip over the table, "Alright!" said Jake. Then all of a sudden, the phone rang, "I got it." said Jake and stretched over to it. He picked it up and held it to his ear. "Hello ... oh hi Charlie ... what's wrong sweety … your not feeling good … alright be right over … love you too, muwa." Jake said and made a kissing sound. He looked back at Finn and frowned, "What's up man." asked Finn, "It's Charlie, she's not feeling so well, she asked if I could come over to see her." said Jake, "I'm sorry man, looks like I won't be able to dungeon crawl with you." said Jake. "It's okay man, your kid isn't feeling well, that's much more than fixing a broken heart, you go to her, I'll just dungeon crawl on my own." said Finn, "Sigh, you promise to tell me all about it." said Jake, "Promise." said Finn, "Okay, I'll see you later tonight." said Jake "Okay." said Finn

Later…

Finn was actually saddened that Jake wasn't coming along with him for a dungeon crawl. He approached a small rock which a flambit was fast asleep on. He bent down to be at eye level with. "Flambin." whispered Finn, the flambit stirred in its sleep and rolled over on its back. Finn sighed and cupped his mouth and shouted "Flambin, thieves are stealing your maps!" said Finn. The flambit jumped awake and scrambled around in a panic. "What, who, where did they go." the flambit rambled. He looked up and saw the young hero, "Oh, it's just you Finn, hey where's Jake?" asked the flambit, "Family problems, couldn't come." said Finn, "Ah, I see. So, what brings you here to my lovely home waking me up?" questioned the flambit, "Yeah, sorry. I came here wondering if you had any maps to a bombastic dungeon, I need to take my mind off of something." he said, "Ah, I think I might have just the dungeon for you." said the flambit and scurried off into a hollow tree. He came out of a hole in the tree with a large map. He tossed it down to Finn and he caught in in his hands. He unraveled it and looked at it. He was amazed by the detailed navigation written on the map. "Wow, where did you find this?" asked Finn, "Oh, I was minding my own business and then I fell down a hole. I was in a large room with ancient hieroglyphs everywhere, and in the center was a skeleton with three books in his hands." said the flambit, "Can I see them?" asked Finn, "Sure thing." he said and went back into the tree. He soon returned with three books in a satchel, he dropped it down to Finn as he caught it in his hands. He looked at them, they looked to be human made. They had a six fingered golden hand print on each of them with the numbers from 1 to 3 on them with a rustic red hard cover with golden edges. The pages spoke extensively about monsters and a place called Gravity Falls. "Wow, and all of this you found in a dungeon?" asked Finn, "Yep, though the page that it was opened to intrigued me the most." said the flambit. He turned to the page that it was originally opened to. It talked about a dream demon and how it can't be trusted. "Wow, well that sells it, a dungeon that has a boss battle, here I come!" said Finn, "Wait, Finn, I don't think that summoning the demon is such a good idea." said the flambit, "Why not?" Finn asked, "Did you read the warning sign?" he asked, "Um, no." Finn smiled, "Read it." Finn flipped to the page and read the part Flambo's brother was talking about. He read the warning sign that read DO NOT SUMMON AT ALL COSTS! "Please Finn, don't summon it." said the flambit, "Fine, fine, I won't." said Finn

Present…

Finn has gone through most of the dungeon by now, and he has not confronted a single monster. He retracted his grass sword and let out a long depressed sigh. He looked at the ground and decided to look at the books the Flambin gave him for the dungeon incase they were there for a reason. He made it through book one when he stumbled over a skeleton and fell into the room that Flambin was talking about. He looked around and saw a giant zodiac on the wall. It was a giant circle with symbols inside the ring and a triangle with one eye and a top hat. Finn thought to himself, this is the boss, wow. He looked at the books and opened book 2 up to the summoning page. "What ever Flambin, I've gone through this dungeon without a single monster, I need something to slay." said Finn he read the incantations out loud determined to slay this thing. "Triangulum, entangulum, vityusfrois dominus menteum, vityusfrois domentus menteombulum." Then a striking pain was struk inside of his heart, Finn collapsed to the ground grasping his chest, it felt like a massive fire was raging within him, then he shoot up on his knees and started chanting "sdarwkcab egassem, sdarwkcab egassem, sdarwkcab egassem, sdarwkcab egassem, sdarwkcab egassem, sdarwkcab egassem, sdarwkcab egassem!" Then the world around him turned black and white, the torches' flames started to slow down, then a triangular portal appeared in front of him and golden fire appeared around the edges, then an eye opened in the middle of it, "Ah, heh, heh, heh, heh, heh, ah, heh, heh, heh, ah, heh, heh!" then everything stopped, and the portal then grew legs arms a bow tie and a top hat. "Ah, I'm back, I'm finally back. Take that Death, the death world can't hold me forever, even if the Pines family erased me from existenz!" said the triangular being soon turning gold. "Hey, over here you dumb isosceles demon." said Finn summoning his grass blade. "Ah, hello there, what are you, some sort of living teddy bear, heh heh, I'm just kidding, I know who you are Finn." said the demon. "What? H-How do you know my name? Who are you?" asked Finn a little frightened by the being knowing him, "Oh I know lots of things, Lots of things. The name's Bill Cipher, and for summoning me, here's a gift for you, here have a head that's always screaming." said Bill and clapped his hands and a large head with a pepper black and sal white hair and beard appeared "AAAHH, AAAHH, AAAHH, AAAHH, AAAHH!" it screamed until Bill snapped his fingers and the layers of skin and flesh was ripped off of the head until all that was left was a skull. "Y-your insane!" cried Finn, "Heh, heh, I'm insane either way kid. Hey nice journals," said Bill "Huh, oh, thanks." he said, "You mind if I take a look at them?" asked Bill, "Hold on, if your a demon, why aren't you attacking me and stuff?" asked Finn, "What? Man, you must have a bad picture of how demons are." said Bill, "Well, yeah, demons are evil beings that need to be slayed the moment they are spawned." said Finn. Bill face palmed his eye and rubbed it, "No, no, I'm not one of those demons, I'm a being of pure energy and knows everything in the known universe." said Bill. "Um that's cool…anyways, I'm going to fight you now." said Finn getting into a proper combat stance. "Okay, whatever you say bear hat." said Bill, and he turned red and his eye turned into a evil black and his pupil turned blood red.

Later...

Finn got back to the treefort mentally scarred. He went upstairs changed into a more comfortable attire. Soon Jake called and told Finn that he wouldn't be home in a few weeks, and that Charlie was really sick. Finn understood the situation. "You sure that you will be okay alone at the house?" said Jake, "Yeah man I'm good." said Finn, "Okay, I'll see you soon." said Jake, "Okay, goodnight bro." said Jake, "Goodnight." said Finn and hung up the phone. Then there was a knock at the door. Finn got up and did a backflip down the ladder and landed on his feet and opened the door. There was a flame guard there with a letter in his hand. "Finn the human." he said, "Yes?" he said, "An invitation to the annual Solar Festival, it will be taking place in the Fire Kingdom, Friday, at 5:30 pm. The Flame King would like you to attend it, she says hello." said the flame guard. Finn took the invitation and looked at it skeptically, "Thanks." he said and the flame guard left. Finn looked at the invitation a little more before going up stairs and he tossed it aside into the mound of treasure he had. He crawled into bed and blew out the candle and drifted off to sleep.

Then he woke up in a field of wheat with assorted debris everywhere. Then there was a echoing laughter through the field. The wheat started to fall to the ground around Finn, creating the shape of the demon that he fought earlier and the field started to glow aqua blue. Then it appeared in front of him.

"Ah, bear hat, how ya dreamin?" said Bill spinning a cane around his finger.

"You, I thought I slayed you!" said Finn pointing at him.

"Ha! You can't kill me, I'm a being of pure energy with no apparent weakness." said Bill

"Really?" said Finn

"Really. Also, how's you little flame?" said Bill opening his hand revealing the letter that Finn had earlier. He was shocked by this.

"How did you get that?" he demanded

"Oh, well since you summoned me, we're now linked through the mind." said Bill

"Well get out." said Finn

"I don't think so, see you soon." said Bill and he clapped his hands and everything faded away.

When Finn woke up he was covered in sweat. He got out of bed and got a shower to clense the sweat off of his body. He changed into his normal clothes, got a good breakfast, and started to work on the house. Over the years, the treefort was starting to deteriorating due to the tree itself growing, daily repairs had to be made around the house. Finn started on the treasure room, he patched up some cracks in the wall with extra wood planks and duck tape. He then worked on the wall that Jake 2 crashed through when FP came to seek his aid to overthrow her father. Then he worked on the bridges. When he was done, he headed up to the roof and practiced his sword fighting skills, going over the moves and exercises that Rattle Balls gave him to work on in his spare time. After he worked on a good two hours on that, he took a break and had a bottle of water. When he chugged all the bottle's contents away, he looked at the vast horizon, appreciating the sun set.

"Finn?" yelled a familiar voice. It startled Finn so much that he fell off the roof and crashed right through the treasure room ceiling. He groaned in pain rubbing the back of his neck. He opened his eyes to see a certain fire elemental run through the door.

"Finn! Oh my glob, are you alright?" said Flame Princess

"Yeah … I'm good." he said getting back up feeling a bit sore.

"I didn't mean to scare you that much I swear." she said

"It's fine, it's fine." he said "What brings you here FP?" he asked

"Well, last night one of our guards didn't return to the Fire Kingdom, and I sent him here with a invitation to the annual Solar Festival, I just wanted to know if you saw him?" she asked

"Well actually I did see him, and he did give me-" Finn went to reach in his pocket to show her the invitation, but realized that he threw it away.

"Um, where did it go?" he said

"What?" she asked

"The invite, I can't find it." he said looking around the room. Flame Princess then saw something buried underneath a pile of treasure. She went over to it and picked it up. It was the invitation, "Finn, I found it." she said

"Oh, thanks, I guess I dropped it." Finn lied

"Finn, I know your lying, why was it in the treasure?" she asked

"Sigh, fine, I just didn't feel like I deserved to come to the Fire Kingdom, to see you, not after..." Finn bowed his head

"Finn, it's in the past, you shouldn't beat yourself up about it." she said

"But I let you down when you needed me the most." he said

"Finn …" she was cut off by the sound of something crashing to the ground.

"Darn it, I thought I fixed everything." growled Finn as he crawled up the ladder. When he got up, he saw the books on the ground, "Darn you books." he said and picked them up and set them on the table. "Finn? What was that?' Flame princess asked as she entered the room. "Um, nothing." said Finn, "Finn, why are you not being honest with me?" she asked feeling a bit hurt by the boy's sudden secretivity, "FP, it's nothing, I swear." "Finn, please, why are you being like this?" she cried.

Finn could not bear to see his ex like this longer. He took the books and grabbed FP's hand and went to his room. He closed all of the curtains and held out the candle to FP. She touched the wik of it and it caught fire. Finn sat down on the bed and took out the journals and opened them up. He patted the bed telling FP to take a seat next to him. She sat down and looked at the books.

"Finn? Are you alright?" she asked

"No, I'm not alright FP, I've been on edge lately. Yesterday, I went on a dungeon crawl. I got this map from Flambo's brother to this dungeon, he gave me these books that he found in it for esurance. When I got there the dungeon was boring as all heck, but when I got to the end there was a summoning zodiac to summon a powerful monster. I needed a good fight, so I opened the book to the page to summon the demon" he said "Did you beat it?" she asked, "Yes, and no." Finn said, "What do you mean by yes and no?" she asked, "It fought me in my head, it made me relive all of my failures and mistakes, he almost broke me." Finn said with sorrow, "But how did you beat him?" she asked, "When he was almost done with me, I saw a memory of you and me, when we were … you know." he said "Finn, I'm so sorry." she said and hugged the young man. He realized that she wasn't burning him. "FP. your not burning me?" said Finn, "Oh, yeah. After the poison wore off, CB took me to the infirmary, just to be sure that I was okay." she said, "And?" asked Finn, "Apperentaly the poison has stabilized by matrix." she said, "That's … good." said Finn. The two embraced each other for a bit more until they broke away. "So, the demon is gone?" she said, "Sadly, no. He now haunts my dreams, and tortures me with my thoughts." said Finn, "Finn, is there anything that I can do to help?" Flame Princess asked, "I don't think you can FP." Finn said.

Flame Princess pondered deeply trying to think of something to lift up the human's spirits.

"Well, maybe we could make you happy again." she said. This brought joy to Finn's heart, could FP be giving him a second chance? "Really?" said Finn, "Yeah, you could come to the Solar Festival." said FP, "Oh, yeah, that could do it." said Finn, "Okay, it starts tomorrow at 5:30 pm, don't be late." she said, "I wouldn't imagine it." said Finn, "Okay, I'll see you later." she said and left for the door, "Okay, bye." he said, "Bye." FP said and left.

The next day, Finn was getting ready for the Solar Festival. this was probably his chance to be with FP again. When he got his suit on from the murder mystery prank that he tried to pull on his friends a few years back he headed for the Fire Kingdom. He was about to leave when he had a horrible migraine. "Ergh, GAW!" he rolled on the floor, overwhelmed by the pain in his head. Then, he was at peace, but when he looked up, he saw Bill sitting in mid-air with his hands engulfed in blue flames. "You again, why won't you leave me alone?" demanded Finn, "Well I can't tell you that bear hat." said Bill, "Then why are you here, I'm going to be late for something!" he said, "Whoa, chillax kid, just hear me out." Bill said, "Ergh, fine! What is it?" Finn snapped, "So, you probably didn't read all of the journals, am I right." said Bill playfully, "No, not yet, there really long books." said Finn, "Well normally when a mortal summons me, they normally have to make a deal." said Bill, "A deal? That's all you want, to make a stupid deal?" yelled Finn, "Yep." said Bill, "Okay. So how does this go?" asked Finn, "Well, what do you most desire?" asked Bill, "Well …" Finn looked at a picture of him and FP together. Bill turned and looked at it "Ah, you want a go at that lady, am I right?" said Bill, "Well, I would like enter her domain without having to have flame shield on." admitted Finn, "Well why didn't you say so?" said Bill, "Well…" "So, do we have a deal?" said Bill putting his hand out bursting into blue flames, "Fine, deal." said Finn and he shook his hand. "So what now?" said Finn, "Now, I rule the night." said Bill, "Wait what?" said Finn. But it was too late, Bill ripped his soul from his body. "What, wha-what did you do to me?" demanded Finn. Then Finn saw his own body starting to rise up from the ground, then he opened his eyes to reveal the truth, he had yellow eyes with snake lined pupils. "Sorry kid, but it's time for the world to hear my name again." Bill/Finn laughed hysterically, "Oh, this can't be happening." said Finn. Bill/Finn started to stagger from side to side as he walked. "Whoo, whoa. Man, it's been a while since I possessed a body. Look at these noodle arms, and why does my head feel so weird." chuckled Bill/Finn and took off Finn's bear hat to reveal his long blond hair. "Wow, look at this, man do you ever cut your hair?" Bill asked, "Why, why are you doing this?" asked Finn, "You've been so infatuated with those journals kid, it's time for me to put an end to it." said Bill, "Race you to the bottom!" Bill/Finn said and leaned backwards and tumbled down the stairs. WHUM WHUM WHUM WHUM! Finn phased through the floor to the bottom. "So, where do you keep those journals, huh?" Bill said, "I've hidden them, somewhere you will - hey! Stop stabbing me!" Finn said to Bill/Finn who was stabbing Finn's arm with multiple knives. "Man, these arms are durable." said Bill/Finn. Then the phone rang, Finn tried to answer it, but his hand kept on going through the thing. Bill/Finn picked it up, "Yellow?" he said, "Finn? Hi, are you coming, it's 5:30 and you haven't showed up yet?" said Flame Princess, "Phoebe! Don't talk to him, that's not me!" yelled Finn, "Sure thing Phebes, I'll be there, say you haven't happened to see my journals anywhere have you?" asked Bill/Finn, "Um yeah, you gave them to me yesterday, remember?" said Flame Princess, "Oh yes, I remember." said Bill/Finn, "Okay, see you soon." she said, "Bye." said Bill/Finn.

The Fire Kingdom…

Flame Princess was anxiously waiting for Finn to arrive, she was a bit perplexed when he asked where the journals where. When she turned around she saw Finn walking through the entrance looking like a stick of gum. He didn't have his hat on, letting his long blond hair wave as he walked. He walked up to her and bowed politely, "Milady." he said, "Aw, stop you." she giggle, "Flame Princess! Listen to me! That's not me! That's Bill! The demon that I told you about!" screamed Finn. "Okay, I'm going to get this party started, could you go and get me a refreshment will you?" asked Flame Princess, "Sure thing Flame." Bill/Finn said and went off to the refreshment table. Flame Princess was liking this new Finn. "Oh come on, why can't she hear me?" yelled Finn, "Welcome to the mindscape kid, without a vessel to possess, you practically don't exist, only I alone can see you." Bill laughed. Finn pondered with this new information, "Without a vessel." he said.

"Welcome everyone, to the annual Solar Festival, we have a special guest with us today, Finn the Human!" Flame Princess said, "We hope that you all enjoy yourselves tonight, let the festivities begin!" she announced. Soon the music was blaring from the speakers and everyone was dancing, chatting, and having a good time. She tried to find Finn in the crowd, then she felt someone grab her hand and pull her into the center of the crowd. She turned to face her partner Finn and stared into his … yellow snake like eyes? That's not right. "May I have this dance?" said Bill/Finn. And they took their hearts to the dance floor.

I say hey

You say oh

Let's turn it on

And here we go

New York, LA

Berlin, Say hey.

To Tokyo, Rio

De janeiro here we go

Hello, Hello

Can you just feel it?

Are you ready to go?

Hello, Hello

Do you receive my echo?

My life is a party

My home is the club

I party like a rock star

Hands up 'till I drop

My life is a party

My home is the club

My stage is the dance floor

Party never stops

My life is a party

My home is the club

I party like a rock star

Hands up 'till I drop

My life is a party

My home is the club

My stage is the dance floor

Party never stops

I say hey

You say oh

Let's turn it on

and here we go

I say hey

you say oh

it's spinning me round

like a yo-yo

DC, Paris

Bell Air, say yeah

To Maleco, Santo

Domingo here we go

Hello, Hello

Can you just feel it?

Are you ready to go?

Hello, Hello

Do you receive my echo?

My life is a party

My home is the club

I party like a rock star

Hands up 'till I drop

My life is a party

My home is the club

My stage is the dance floor

Party never stops

I say hey

You say oh

Let's turn it on

and here we go

I say hey

you say oh

it's spinning me round

like a yo-yo

Hello, Hello

Can you just feel it?

Are you ready to go?

Hello, Hello

Do you receive my echo?

My life is a party

My home is the club

I party like a rock star

Hands up 'till I drop

My life is a party

My home is the club

My stage is the dance floor

Party never stops

I say hey

You say oh

Let's turn it on

and here we go

I say hey

you say oh

it's spinning me round

like a yo-yo

She was having the time of her life, she hasn't felt this happy since she and Finn were dating. When the song ended, she was out of breath. "Whoo, when did you learn how to dance so good?" she panted, "I've had practice." Bill/Finn smiled, "Okay, you go on without me for awhile, I'm going to go freshen up." she said and left for the washroom. When she got in, she splashed some magma on her face and exhaled deeply. Then out of the corner of her eye, she saw the displayed knight armor walking towards her. She turned around and was frightened by this anomaly. She screamed and blasted the armor with a roaring fire. "GAW, Flame Princess! Stop! It actually hurts!" cried a familiar voice that she could ever forget. "Finn?" she said and stopped melting the armor and dashed to its side. "Finn! How are you in there, and why are you in the girl's washroom?" she said and removed the helmet to see nothing, she gasped and dropped the helmet. "H-h-how?" she stammered, "I'm trapped in a place called the mindscape, and I can only commune with the physical world if I possess a vessel." said armor Finn, "But, I was just dancing with you?" she said, "That's not me, well kinda, but mostly no." Finn said, "Finn, what is going on?" exclaimed Flame Princess, "Bill came back." he said, "Who?" she said, "The demon that I told you about, the one that I tried to fight." Finn said, "But … how did this happen?" asked Flame Princess, "When I was about to leave the house Bill showed up and wanted to make a deal with me, kinda like making a wish." said Finn, "and I assume that didn't go well." said Flame Princess, "Not at all, I … I wanted to make a deal to make me fireproof, so I could visit you without having to have flame shield on everytime." said Finn ashamed of his actions, "Oh, Finn." Flame Princess said putting her hand on the armor, "When I shook his hand, he ripped my soul from my body and possessed it, and he wants to destroy the journals or something." said Finn, "So that's why you, erm, sorry, Bill asked about them on the phone." she said, "Yeah, and we need to get them before he does." said Finn, "You know where you put them?" he asked, "Yeah, in my room." she said, "Okay let's go get them." said Finn and opened the door for the princess.

They made their way to the royal chambers. When they got their, Bill/Finn was already there with the journals in his arms. "Sorry flame you lose!" he maliciously laughed and protruded a firearm from his pocket and put it to Finn's head. "NO!" yelled Flame Princess, "Ah, so you still care for this fleshy body?" said Bill/Finn. Flame princess fell to the floor on her knees and nodded in defeat, "Yes." she whimpered, "Ha, ha, but why, didn't he let you down when you needed him the most, and now you want to save him after that? Like seriously? Who would sacrifice everything to save anyone?" said Bill/Finn. Flame Princess mumbled something under her breath, but it was nothing but a puff of smoke to Bill/Finn. "What was that Flame? I couldn't hear you." said Bill/Finn, "I said, Finn would." she said as her eyes burned in a blood red color and launched herself at the possessed human.

He dropped the gun and started rolling on the ground wrestling with the fire queen. He grabbed her neck and ignited his hands in a blue flame, to Flame Princess's surprise it actually burned her. She fell backward and grasped the burn marks on her neck rolling in pain. Bill/Finn grabbed the gun and pointed it at Flame Princess's head and smiled.

"Hey bear hat, what's heartless, firey, and covered in blood?" said Bill/Finn looking around for Finn's astral form, but it was nowhere to be found. Then he felt a sharp pain in his left arm. He looked down to see a flaming spear sticking out of his shoulder. He dropped the gun and fell to the ground. "Agh! Too much pain! Too much pain!" Bill/Finn yelled. He looked up and saw a half melted fire knight towering above him with no head, "You." it said with the voice of Finn the Human, "You-you idiot, when I leave your body, you will feel the same pain that you've inflicted on me!" yelled Bill/Finn, "Totally worth it to save the girl I love." said Finn ripping the spear from Bill/Finn's body. "Have it your way then." said Bill/Finn as he left Finn's body. Then Finn reentered his heavily battered body. Flame Princess got up and crawled to Finn's side taking his pulse, it was silent, "Finn? Finn! Finn please wake up! I need you!" Flame princess screamed in his face. Then she was kicked in the gut by the fire knight's foot. She looked up and saw the armor was still possessed, but by Bill. This time, crimson red flames blazed out from the collar creating a evil eye, "Your going to need him more than you think flame!" boomed Bill as he raised the spear ready to end the Flame Queen's life. Then out of the blue, multiple slashes cut through the armor, and it was still. Then it started to fall apart into the shape of Finn's head and the blazing flames disappeared. Behind the armor stood a blood covered Finn, holding his grass sword in hand. "Whoo! Take that you scrap heap, Finn Mertens I back in action!" he said in a victorious voice right before he started to see black spots in his sight, "Nope, nevermind. Tell Bill he can have my body back, I'm done using it." said Finn as he fell to the ground and his grass sword band detach itself from his arm. "FINN!" Flame Princess screamed

3 Days Later…

Finn soon woke, feeling everything in his body hurt. He looked around the room to see that he was in the royal chambers of the Fire Kingdom. When his head turned to his right side, he saw the fiery princess asleep at his side with her neck in a cast. She started to stir and awoke to see Finn. "Your awake." she said with such joy in her voice with a hint of pain. "Flame Princess, are you okay?" Finn asked with a concerned tone, "Am I okay? You should be asking yourself that, your so lucky to even be alive." said Flame Princess. Finn looked down and saw his entire left arm in a cast, his leg elevated off the bed, he could feel his head covered in a bandage, and multiple burns over him. "Ugh, did Bill cause all of this?" asked the human, "Well the knife wounds in your arms was Bill, and so is the broken leg. But the shoulder wound was you, and the head injury and burns was me." she said with shame, "Hey, Flame Princess, you hurt Bill, not me, remember that, it's not your fault, it's mine." Finn said. "What, no, it's not your fault, not at-" "No, it is. I'm the one that let my self pity get the better of me and summoned Bill in the first place. I'm the one that made a deal with him and allowed him to take control, I allowed him to hurt you, this is all my fault." Finn said, "Everything is my fault."

She couldn't agree or disagree with him. Yes he did ignore the warning in the journal, and he did let his guard down, but it was also her fault too. "No Finn, it's my fault." she said, "What?" he said, "I'm the one that didn't thank you for saving my Kingdom, I didn't even give you a second chance. If there's anyone to blame for all of this, it me." she said. Finn tried to sit up, but his pain would not allow it. So he settled for lifting the fiery girl's chin up to see him. "Flame Princess." he said looking into her eyes that were now welling up with magma, "When you needed help, I let you down, I was so caught up in trying to impress you that I got us captured. And yes, it was kinda hurtful when you didn't notice me leaving. So in a way, heh, this is both our fault." he said. She smiled at his response and gave him a tight hug. "Ow, ow, ow, pain, pain, pain." Finn squeaked, "Oh my glob, sorry, sorry." she said and pulled away. The two looked into each other's eyes, it was quite all around until Flame princess broke the silence, "Finn…" she exhaled with deep thought, "Yes Flame Princess?" he asked, "I'm, ready to give you that second chance." she smiled. Finn's face was soon taken over by a wide smile and he leaned forward with all of his might and kissed the fiery ruler. "Would you take that as a yes?" he asked, "Definitely." she said with tears of joy flowing down her cheeks. And the two teenagers embraced each other for as long as they could until fatigue took affect and they both drifted off to sleep.

THE END

I hoped you all liked this story. I've been recently watching Gravity Falls and Adventure Time, and after I watched the episode "Sock Opera" and "The Red Throne" I thought to myself "What if Finn was possessed by Bill Cipher and an epidemic happened that brought the two love birds back together." I thank you all for reading my story … that is if you are reading this part.

LOL XD

Honorable Mentions:

Distant Phoenix and his latest chapter in Time's Downfall. I strongly suggest it to all of you Destiny and Adventure Time fans out there to read his story, for he is one of the many writers that fuels my ideas for my other story: Destiny The Last Guardian.

209riveraiseral for his latest chapter of "Adventure Time Insurrection" his story is one of the key concepts of my story as well, and is a good friend of mine. If you dear readers are the ones dying to see Finn and Flame Princess to get back together, go and check out his story!

Updates:

Destiny The Last Guardian:

Chapter 6: The Infinite Forest (near completion)

Chapter 7: Saint 14 (coming soon)

Star Wars: Infinite Galaxies (coming soon)

Adventure Time: Quest For Finn (sequel to Destiny The Last Guardian)