Warning: I do not own Adventure Time. If I did, Adventure Time with Fionna and Cake
would have a spin of series portraying the love of Marshall and Fionna. So, I mean, I obviously don't own squat.
Author's note: Also, this is still my first story. So please take that into consideration when reviewing me. That being said, I thank everyone who reviewed me. I love constructive criticism. It helps me a lot due to my little knowledge. Thank you Ashley, 2cuteInufan06 (Oh thank you for the pressure), Charles Lehmann, and purpledragon6. A special thanks to raisinbrandy for helping me, and giving me advice. I tried to space it out I hope to have done better
I really hope I don't disappoint anyone. This story is going to go like this: Marshall past, Fionna present. The next chapter will be Fionna in the present, three years from this. I hope this does not confuse anyone. I also hope this chapter is not too long, hahha.
Please review and enjoy!

3 years, one week ago:

"Hey bunny" I said as I floated down towards her. She was walking towards her house, dressed up very nice, with a little Cake on her shoulder. "Why do you look so good?"
She looked up at me annoyed, oh, is she on her days?
"I hate that nickname you know"
I plopped on the ground. "Sorry, what's up? Why do you look so dolled up?"
She ignored me. Her blue dress ruffled.
"Fiooooo" I sang.
She walked up to her tree house. "What?"
"Did I miss something?" I asked concerned.
She shrugged, still annoyed. "No you didn't. I'm going to go inside now"
I looked confused. Was this one of those girl things I wasn't going to get?
Cake looked at me arrogantly from her shoulder. "You forgot something."
Fionna quickly blushed. "Shushers, Cake!" She yelled and shut the door.
I stood at the door for a few minutes confused. What would I forget?
Cake propped open a window near the door. "You seriously forgot boy?"
"Forgot what?" I said a bit annoyed.
"You know that thing… You don't do, because you're a creepy vampire?"
"Enlighten me" I smirked.
She rolled her eyes. "Age, bonehead, you don't age."
"And?" I sang.
"Fionna does."
I still didn't understand… I cocked my head at her.
"So every year on the anniversary of her birth… there's a-"
"Birthday!" I exclaimed.
Cake nodded. "Good job, genius… and you claim to love her."
I blushed. "What! No I don't!"
She closed the window, laughing. My redness stayed on my face. I had forgotten her birthday… She was turning sixteen, and I forgot. What kind of friend was I?
How could I not remember? I should have because of how I feel about her.

Oh right, I was trying to ignore those feelings… That could have been the cause.

Her dress… Prince Gumball had a party, and I didn't show up.
Had he mentioned it before?
"Hey Marshall… We're having a party for Fionna next week. I'm pretty sure she'd love if you came. "
I shushed him. "Shh, Heat Signature is on…"

I blinked. "Damn it."

I floated off the Candy Kingdom, feeling guilty. I floated into Gummybutt's window without care of the guards.
"Hey PG" I said behind him. He jumped up at my voice, immediately falling when tripping over a rug.
"Marshall! What the Cabbage are you doing here?"
I ignored his question. "I have a problem"
Gumball stood up, flattening his pajamas which were pink with a candy design. If I wasn't here for help, I would have said something by now.
"What do you want?" He said a bit irritated.

"Fionna, it was her birthday. I completely forgot."
He nodded. "So that's why you didn't show up! I reminded you though! How could you forget"
"Forget about that. How do I make it up to her?"
He shrugged. "I don't know"
"What do you mean you don't know!" I cried out. "You're a scientist!"
He nodded. "Well yes, but we haven't mastered the science of girls just yet. Girls are… complicated"
I collapsed on his bed. What was I going to do? I couldn't count how many times Fionna had helped me. Here was the perfect opportunity to repay her, and I completely blew it.
"I bet some presents would be nice" PG said, after looking at me. "As a start…"
I got up and quickly bro-hugged him. "Thanks dude, thank a lot."
He pushed me away, awkwardly. "Anytime… Now get your immortal patoot out of my house before I call my guards"
I smiled and bowed my head, before finally floating out of his room.
I now had a plan.

Cake dragged Fionna away from an adventure.
"Dude what are you doing? We almost defeated that guy!" She said trying to push open Cake's arms.
"Shh, That guy was not causing any beef and you know it Fionna"
She sighed into her fluffy arms. "I needed to fight out my emotions somehow…"
"because of how you are disappointed with your crush"
"Marshall Lee is not my crush!" She blushed.
Cake smiled all-knowingly. "Maybe I hadn't been talking about Marshall"
Fio stayed quiet, embarrassed.
"Well, you're fruit bat wanted me to bring you back."
She looked up at Cake. "What?"
She set her down in front of me. She tried to look mad at me, but she was also confused and a little happy to see me.
"I forgot your birthday"
She mocked me. "Oh I hadn't realized."
"So" I smiled, "I have come to make up for it!"
She looked at me trying to pretend not to be interested.
"Today, I will take you out to have fun, and tomorrow, and the next day. Every day this week is your birthday. It's Fionna's birthday week."

She finally smiled at me. "No you don't have to do this… I was acting really wrongteous, I'm sorry"
"No you weren't. You're a really sweet kid, and I can't believe I forgot my best friend's birthday."
"It's alright" She laughed. "It's just a birthday. As a vampire, I think you're allowed to forget those…"
"Well how about, I do this to repay you for all the great things you've done for me…"
She looked confused. "You've done plenty of things for me Marsh…"
"Oh come on you hard head" I said grabbing her hand, and floating off.
That's how the week went. Every day, once night came, I'd take her out and do something. , each day ending with a present. It was hard to think of one present, imagine having to give her seven? It was a difficult process, but for her I'd do almost anything.

The first night, we ran with whywolves for the whole night. When we got tired, we lazed and watched the stars and talked. At the end of the night, I gave her a book of adventures I think she would love as she was a great adventurer herself.
The second night we rummaged through and found some great movies. We watched them at my place, making jokes and laughing as we lay on a blanket on the floor. (My couch was still too uncomfortable. At the end of that night, I gave her the movies and a nice t-shirt I thought she would like.

The next day, she showed up in my t-shirt. I loved it on her.We went to the Ice Kingdom to prank the Ice Queen a few times… Then we went on a pranking spree throughout the whole night. At the end of this night, I gave her a weird camera I had laying in my closet. The pictures came out of the camera, and you need to shake the picture to actually get it to come out. She very much enjoyed it, quickly taking a picture of the two of us.

The following night, she showed up with the camera around her neck. She'd take a picture with her camera every time the lighting was just rigI took her to the ice cream kingdom, which she went bonkers over. Her eyes went left and right. She was in love with the ice cream. I was not jealous.I still can't figure out how she stomached that much into her belly. Her present that day was a bracelet I'd stolen from the Ice Queen. It was the loveliest thing, it never melted, and it was not cold on her skin. She loved it ever more, and as she excitedly yammered about it. I noticed how her eyes shone just like it.

The fifth night we went to the Music Kingdom. She forced me to dance with her, saying how we would have danced at her birthday party. I made sure to quickly pull away when slow music came on. I didn't want to know how I would feel during that dance. She talked to some friends, Sophie and the Jazz King, before we went on stage to play. As that was what was always done in the Music Kingdom. We'd played many songs before, and so we played many of those now. Our voices always harmonized, and people loved that. I loved that.The present of this night was something I found within the Music Kingdom. A music box that was custom made. It had us performing and playing our songs. She went mental about it. I couldn't help but blush.

The penultimate night, we played dress up. A strange, strange thing, I know, trust me. For a long time though, she had wanted to take a peek through all my clothes. I'd kept telling her no… but I guess now was the right time. Her present for that night was a new dress to wear the following night, the last night of her birthday week. She couldn't have been more eager, pressuring me to tell her.

The final night, I decided would be a fancy affair. I had Gumball arrange us a nice place to take her to dinner. He thought it was really strange for me to do this, and it was. I was doing it for two reasons though. One, I wanted to see her in a dress not mad at me. Two, this would be the closest thing I had to a date with her. She couldn't have been more immature during the dat-, I mean dinner. I couldn't have been any happier.
"Did you enjoy your birthday week?" I asked.
She smiled chomping on her cake. "Best week ever… How are you going to top next birthday?"

I laughed. "I'll figure it out…" I had a platter of strawberries in front of me.
She had her chin on her palm, and her eyes glazed at me. If I hadn't know any better, I'd say she looked like she was infatuated with me… but she wasn't.
"You haven't been this awesome to me in years"
That's because I'm running away from how I feel about someone who will leave me.

I ignored the statement. "Are you ready for your last present…?"
She nodded eagerly and I pulled it out from underneath us. I went all the way back to the Nightosphere to get it. It was a flower. The cheesiest thing ever, but it was amazing for one reason.
"It's immortal"
It also was the prettiest thing in the world, besides Fionna.

She laughed in adoration. "It's amazing Marsh. Where'd you get it?"

"Just found it around"
As she held it. She looked up at me. "Can I ask for one more present?"
I looked at her confused. "Sure. What is it?"
"Can you tell me how you feel about me?"

If I could have controlled the world for that very second, my head would have exploded. She must have figured it out… She must have seen the way I look at her. She's going to tell me off, I know it.
"Uh, I have to go" I stood up.
She looked surprised. "Marsh, No! Wait!"
This was going to end badly one way or another. I had to go. I couldn't say anything.
"I'll see you soon alright kiddo?" I began to float out of the room.
"Marsh!" She yelled. "I didn't mean it!"
I floated out of the room, getting a lot of questioning looks. I left the kingdom.
I'm Sorry Fio.