Disclaimer: I do not own Adventure Time. I only own the Ocs.

A/N: Hey, this is Kman134. I apologize for not being around for a while, but I had some stuff to do with college applications and other works on . Anyways, here's an Adventure Time Fanfic and P.S., This entire fic is going to be in anime-style because I have embraced the Otaku lifestyle.

Prologue

In the tree fort at the Grasslands, the 15-year-old boy, Finn, was filling his backpack with supplies. It looked like he was preparing for a trip for he was packing, not only extra clothes, but, also, food and other necessities. After he was done packing, finn Climbed down to the living room and was met with the eyes of his best friend/adopted brother, Jake who was sitting at the table, enjoying a plate of bacon-pancakes.

"Hey, Finn, where are you going with that bag?" Inquired Jake, puzzled by his brother.

Finn turned his attention to Jake while his hand was placed at the front door. He replied with a deep sigh, "I'm going on a journey across Ooo and I'm doing it...alone. I don't know when I'll come back, but by the time I'm done, I'll learn how to be the greatest hero in all of Ooo."

"Wait, Finn!" Jake attempted to stop his brother, stretching his body and blocking the front entrance. "What do you mean you're leaving?! What is this all about?!" He tried preventing his brother from leaving, but it was futile as Finn was able to get pass his best friend and stepped out of the door, but before he completely left, he said his final words.

"Jake, since that time when the Lich killed billy, I've realized how one of the greatest heroes in all of Ooo is no longer with us and so, now, it's up to me to fully protect Ooo. Not from the Lich, not from Ice King, but from something even more destructive that could threaten our home. So, I must travel the land and learn what I can to improve my skills. 'Til then, I'll come home."

Finally, Finn marched on until he was completely invisible to Jake's vision. Jake couldn't help but feel depressed that his best friend was not gone. BMO was standing next to the bulldog and started crying as virtual tear fell from his/her screen.

0000

At the Candy Kingdom, Jake ran inside the castle with beads of sweat dripping from his forehead. It was fortunate that Princess Bubblegum was there conversing with Marceline on some important issues. PB and Marceline noticed Jake running and stopping in front of them.

PB was dressed in her usual attire and hair style, having her left bang hanging down in front of her eye, while Marceline was dressed in a dark gothic lolita dress with fishnet sleeves, black & red striped stockings, and a big, red bow on her waist.

"Jake, what's wrong?" PB asked with concerned eyes. Jake was trying to calm down his breathing, having both of his paws on his knees and staring down at the floor.

Regaining his posture, he looked at PB with wide eyes, saying, "Finn is gone! He just left the tree fort with a full backpack and just walked out!"

The girls exclaimed "What" from hearing such info. Jake then added, "Yeah, but that's not the worst part! He's traveling all over Ooo and he won't come back until he learns how to be a hero great enough to protect Ooo from any threat!"

Everyone in the castle was shocked from hearing this, but no one was more staggered than Princess Bubblegum.

"Bonnie, you okay?" Marceline asked with her glowing, red eyes looking at her frenemy.

Princess Bubblegum snapped right out of her deep thought and turned to Marceline, "Y-yeah, Marcey, I'm fine." PB tried to hide it behind a fake smile, but the Vampire Queen could tell that her friend was troubled. Then she thought to herself: Oh Glob, Finn, what's happening to you?

0000

Somewhere in the grasslands, almost close to the Ice Kingdom, Finn was walking towards the burning home of his girlfriend, Flame Princess. "FP!" he shouted. Out of the house came Flame Princess.

Dressed in a casual, yet royal, type dress, consisting of a short, flame retardant black coat over a light-brown dress with tan laces on the bottom and collar of her dress and wearing white socks reaching up to her shins and red slippers, Flame Princess had her hair tied in a fiery ponytail.

"Finn, what are you doing here?" She inquired her boyfriend. Looking at his face, she could tell something was up. "What's going on, Finn?"

"Flame Princess, I'm going away for a while."

"Going away? What do you mean 'going away?' Where are you going, Finn?"

"I going to travel across all of Ooo and I won't come back home until I've become a hero strong enough to protect everyone I care about from any new threats."

Flame Princess was shocked by this sudden turn of events. After saying 'goodbye', Finn turned around and was about to walk away. Reaching her hand out, Flame Princess cried while tears of lava began flowing down her cheeks, dripping down and singeing the grass, "Finn, please, don't go!? What about your friends; what about us!?"

Walking, Finn stopped after hearing what his girlfriend just said, clenching his fists and letting out another deep sigh. Looking back, he retorted, sadly, "Everyone will just have to handle the situation until I return." Then he continued walking, leaving Flame Princess on her knees, wallowing with a river of lava tears dripping off her cheeks and falling on the grass.

I'm sorry for doing this, Flame Princess, but it's the only way I can be stronger Finn thought, apologizing to the princess. Even though he walked with pride, he was able to shed one tear from his eyes.

Finn was now gone and had traveled throughout Ooo for three years, discovering new places and meeting new people along the way.

0000

3-years-later, Finn had grown up into a strong, 17-year-old man. His wardrobe had changed, as well. Instead of wearing his usual bear hat and blue shirt, he was wearing a white shirt under a light blue hoodie with his white bear hat stitched on the back of his collar, which he wore over his head. His place had changed, too, appearing longer and having more pockets and, instead of his usual shoes, he wore a pair of strapped boots.

Standing in front of the Tree Fort's front door, Finn smiled and pulled his hood back, revealing his spiky blonde hair. God, it's been so long since I saw everyone. Geez, I wonder how everyone's been since I left and I wonder how they'll react when they see me. Opening the door, Finn waltz right in and mentally prepared himself for what came next.

To be concluded

A/N: Well, hope you have enjoyed the prologue. Please, send in positive review and if you have any suggestions, speak up if you like. Also, I would to say that this fanfic was inspired by the works of Ziqman and sybcj on deviantart whose Adventure Time doujinshi's gave me the idea to make this, which I am a huge fan of.

Note: This fanfic sets in an alternate universe where most of the events of Season 5 have not taken place. in other words, Finn and Flame Princess are still together, Jake's puppies haven't been born yet until Finn returns, and etc.

Finn's anime appearance in this series is modeled after Ichigo Kurosai from Bleach, Naruto Uzumaki from Naruto, and Monkey D. Luffy from One Piece, excluding the scar.

Bubblegum's appearance is modeled after Moka Akashiya from Rosario Vampire and Marceline's is modeled after the outer Moka.

Flame Princess is loosely modeled after Orihime and Hinata Hyuga, although her personality will change to that of a tsundere.