Chapter 1.
Finn had just revealed a long held secret to his brother, Jake. Finn wanted to become a girl and be called Fionna. Jake looked shocked, worried and confused. But when he opened his mouth, he said what Finn had hoped he would. "Well, uh, Fin-Fionna, I guess I have a sister now." Fionna smiled and hugged her brother tight. "Thank you thank you thank you!" she yelled. Jake returned the hug but remembered something else. "Listen, Fionna, I might be ok with this, this, whatever this is, but everyone might not be. I want you to know that whatever happens, you're still my sister. Okay?", he said. She thought for a moment on what he said. It was true; this was not new to her, but it was a new concept to the rest of the world as far as she knew. "Okay, Jake.", she told him.
After all this took place, Fionna went to bed and thought of who she should tell next. Marceline? PB? BMO? FP? She decided BMO should know next, and Marceline would know the next day. "Hey Bmo! I have to tell you something!" the little gaming device started toward Fionna. "Yes, what is it Finn?" "Well, that's the thing. It's Fionna now." The little robot was quiet for a bit, then said,"Oh, ok. I'll update your name now!"
The next morning, Fionna called Marceline and asked if she wanted to jam. Of course she did, she'd love to practice with him. On her way to Marcelines house, she wondered what the vampire queens reaction would be. Glob I hope she'll still talk to me, she thought. As she reached Marcelines house, she heard a bass thumping through the houses walls. Huh, she started without me. Weird. "Knockety knock! Marceline! I'm here!", she yelled to be heard over the music.
Inside she saw two people floating in the air and playing bass guitars. "Oh hey Finn, there you are. This is my cousin, Marshall Lee." Marceline said, gesturing towards the lanky, grey skinned boy. He flashed a peace sign at Fionna and she returned it with a smile. "Hey, Marcy? Can we talk for a second? In, like, private?" she asked rubbing her arm. Marceline cocked her eyebrow, but gestured towards the ladder leading towards her room. "Lead the way."
As Fionna climbed the ladder, her heart was beating hard and her thoughts were racing. When Marceline entered the room, she closed the little trapdoor behind her. "Okay, hero, what is it that you want to talk to me about?", She asked crossing her arms. "W-well, h-here's the thing, we-we're friends right? I can, like, trust you with things right?", Fionna asked nervously, cursing the way she stuttered. Now Marceline was worried. "Of course, what is it?"."Well, I'm, um, I'm a girl on the inside. Can-can you call me Fionna from now on?". She asked with her eyes closed.
Marceline was silent, but the Fionna felt arms wrapping around her. She opened her eyes to find Marceline holding her tight. "Of course I will, you big dork. Now come on, lets jam." Marceline let go and opened the trapdoor to find Marshall Lee floating lazily above the sofa. "Ready?", he asked, one eye open. "Yep, just had some stuff to clear up." Marceline replied.
Later that day, Fionna went to the Candy Kingdom to tell PB. She found the princess just beginning a new experiment. "Hey princess, can we talk for a sec?", Fionna asked . "Sure thing, just a second Finn.", Bubblegum told her. It had just occurred to Fionna how much hearing her old name bothered her. It was an intense dislike of it, almost hating it. "So, what's up?". "Well, um, I'm a girl on the inside and my name is Fionna and not Finn", she said in a rush, surprised it was getting easier to say. The princess blinked several times, and then squinted and said, "Well, okay, I guess. If that's how you feel, I suppose that's who you are then."
Fionna smiled wide and hugged the princess tight and ran off to tell more people. Who was next? Flame Princess, she supposed. She walked all the way to the Flame Kingdom, and found Flambo and asked for a flame shield. When she received one, she headed towards the palace.
"Hey FP, how are you?", she asked of the orange monarch. "Things are going well, how are you today?", the ruler replied. "I'm pretty well...Hey, can we talk in private? I need to tell you something." "I suppose so, whats up?", FP asked. "I'm a girl on the inside, and my new name is Fionna. Are we still friends?". Taken aback at this revelation, Flame Princess considered what she had just been told. "Of course, but may I ask what makes you think that?".
Finn considered the question for a brief moment. "Of course. First, the name Finn just sounds wrong to me. I feel fake, like I'm in someone else's body. It just doesn't feel real, you know? Like, this isn't the real me." Flame Princess considered this for a moment before nodding in agreement; she could understand feeling fake.