Don't own anything, just the story plot.

Finn is 20. Legally an adult. I'll admit, I'm not an expert on the legal system of Ooo, but I do know Finn isn't 13, which doesn't make this one-shot shocking and awkward XD

~AT~AT~AT~

Marceline came over a lot. That was cool, Jake didn't mind, after so many years the vampire queen grew on him and he liked her. Yes, she still scared him, but he wasn't about to admit that.

Now-a-days, Jake had settled down and even got married to Lady Rainicorn. It was a momentous wedding, celebrated in the Candy Kingdom thanks to Princess Bubblegum. Finn of course was his best man, because now the human boy was not a kid, but a man. Jake was so proud of him.

Now Finn lived in their tree house alone and Jake lived with Rainicorn, but every weekend Jake would stay at the old tree house. Lady Rainicorn was such a good wife; she understood the bond between a boy and his dog… although now it should be the man and his dog. Finn was tall, much taller than Marceline, and lost his little boy pudge to replace it with hard worked muscle. He still wore his hat but now long locks of blond hair stuck out. His voice was deeper and although he still looked lanky he had impressive upper arm strength.

It was that deep voice that started it all, actually.

Jake was downstairs, giving Marceline and Finn alone time while the two watched their favorite TV show. It was late at night but it was also Saturday, so who the glob cared? The dog was resting on the couch with a belly full of everything burritos he had for dinner. He had a thought; was Finn hungry?

"I better get off my lazy butt and ask," Jake said to himself. He walked up the stairs and saw Finn's bedroom door cracked open. The tree house had been remodeled when Finn was sixteen so the boy could have his privacy. That was when he was going through the awkward stage. "Finn," Jake called out.

There was no answer. He needed to walk closer. Jake trudged along the hallway. "Finn," he said again.

Then the dog heard a stressed and loud, "So close!"

He then heard Marceline's voice as she said, "It won't fit, it's too big!" Her voice was whined but also held excitement in her tone.

Jake stood there awkwardly. Just what is going on? He wanted to open the door but he hesitated. What if something he didn't like was going on?

"It's got to fit Marceline just let me try it."

"It's too big Finn."

"Well it's the only one I have."

"Uh! You're so frustrating!"

"I'm trying to hurry babe."

Now Jake had a somewhat disturbed look on his face. Was Marceline referring to… was Finn talking about… they had to hurry because…? Jake should've walked away. But he couldn't. He just couldn't. Were they doing what he thought they were doing?

"Here," Marceline said, "Let me try to slip it in."

"Be careful!" Finn exclaimed.

"I am being careful!" the vampire snapped back. "This isn't something I would want to mess up. We've been waiting for this for a long time."

Finn laughed slightly. "I've been waiting ever since I was a kid."

Jake's jaw dropped in horror. How could Finn say that?

Marceline made a grunt sound. "I think I got it."

"No, wait," Finn objected, "You turned it the wrong way."

There was a silence and then both of them cheered, "YES!"

That was it. Jake barged through the door angrily, "WHAT ARE YOU TWO DOING?"

Marceline and Finn turned their heads in surprise. "Watching TV," they both then said innocently. Jake saw that Marceline was sitting on Finn's bed while he sat on the floor.

The dog's expression dropped. "But… what was all the bickering and yelling?"

Finn gave Jake a confused grin. "The remote needed new batteries and Marceline thought they were too big and we needed AAA batteries, but I got it to fit with AA."

Marceline figured out what Jake was thinking. She grinned slyly. "We're watching Wizard Battle in HD," she said. "You've been waiting for this moment since you were a kid, right Finn?"

"Yup!" Finn exclaimed happily.

Marceline shot Jake a scary look. "It's not nice to listen in," she winked. And then she leaned over and planted a kiss on Finn's cheek.

Author's Note:

This was rated M to be safe. Should I be embarrassed? Aha it took courage for me to post this, I'll just say that. Please review. Or not. Ahahaha. I'm so… shocked… I wrote this. Poor Jake. XD