Matchmaker Flame Princess
I can thank the episode "Burning Low" for inspiring this.
Please, if you're a strong Flame PrincessxFinn supporter just leave, and don't leave a bad review if you're not happy about what happens, because this is my story, it will go as I write it, and if you don't like it, you don't have to read/respond to it. Okay? Okay. Let's go.
Flame Princess was sitting by her new house, which now had a metal canopy over it.
She was waiting for Finn to come over, having summoned him because she needed to talk to him.
For over a month now they had been together, but as time went on, Flame Princess started to doubt the relationship. She felt that being with Finn was not worth accidentally burning him constantly.
Soon, Finn showed up with Jake.
"Hey, Flame Princess," Finn said happily, "it's good to see you again."
"Yeah," Flame Princess replied, "and...you brought Jake."
"He was my ride." Finn stated.
"I get it," Flame Princess said awkwardly, "but, I really need to talk to you...privately."
"Don't worry," Jake said, "I'll leave you two be."
Jake then walked further away.
Before Flame Princess could stop him, Finn gave her a hug and a kiss, resulting in yet another burn. He was visibly in pain, but he forced a serene expression on his face.
"I missed you..." Finn said.
"I have to stop you right there," Flame Princess said, "this is important."
Finn looked on curiously.
Flame Princess sighed deeply.
"Finn..." the Fire Princess spoke, "you know I like you...a lot, I really do."
"Yeah," Finn replied, confused, "I like you too."
"I know," Flame Princess spoke solemnly, "and it's been fun, but it's also been...complicated."
"What?" Finn responded.
"What I'm trying to say is..." Flame Princess voiced dismally, "Finn, we can't...I don't think we should do this anymore."
"What..." Finn uttered, "wait, are you...are you breaking up with me!?"
"I'm sorry, Finn," Flame Princess said unhappily, "but it's just so...exhausting and nerve-racking, what with the burning and the unstable physical matrix and whatnot."
"But, but like I said," Finn responded anxiously, "I can handle it."
"I know you think it's worth it, Finn," Flame Princess said depressed, "but to me it's not worth hurting you all the time, every unprotected hug and kiss gives you third degree burns, and in order to get one without burns we either have to wrap you in tin foil or cast the Flame Shield on you, and that's just not fair or fun."
"So, it's worked well so far!" Finn argued.
"Aside from that, I almost scorched the entire world from one kiss," Flame Princess affirmed, "and just last week you got heat stroke while with me."
"I didn't drink enough fluids that day," Finn asserted, "that had nothing to do with you!"
"Still, it's not fair to put the world and everyone who lives on it in jeopardy just so we can be together," Flame Princess said, "as a hero, you should know that."
"I do," Finn said sadly, "but, I really really like you."
"And I really really like you too, Finn," Flame Princess attested, "this has nothing to do with that, it's just that...I don't wanna burn you anymore. I care about you and always will, but that's why I'm doing this, because I care about you too much to leave another burn on your skin."
Finn stood speechless, his eyes wide and shimmering.
"I...I understand." Finn said hesitantly, holding back tears."
"I'll always be on your side." Flame Princess assured.
"Okay..." Finn replied forlornly, "but...what am I supposed to do now?"
"Now comes the good part." Flame Princess said.
"There's a good part in all this?" Finn asked flatly.
"Yeah," Flame Princess said blissfully, "because now, I'm gonna find you a new girl."
"A...new girl?" Finn replied quizzically.
"Yeah, someone better than me;" Flame Princess expresses, "you need someone pretty with real skin that you can hug and caress without getting burned, someone with real hair, long hair that you can run your fingers through, someone who can protect you and kiss you without the risk of turning the world to ash."
Finn looked on curiously.
"I promise," Flame Princess avowed, "the one I find will be way better than me."
"If you say so;" Finn said somberly, "well I guess I'm gonna go home now."
He choked back a sob.
"Bye...FP." he said pitifully.
"Bye, Finn." Flame Princess said softly.
Finn caught up with Jake.
"So how'd go?" Jake asked.
"She...she just b-broke up with me, Jake." Finn answered sorrowfully.
"Oh man," Jake replied, "why?"
"She said that she wasn't good enough for me and that she was tired of burning me and that it wasn't fair I had to wear tin foil to get a hug," Finn explained, "she said we weren't worth risking the safety of the world and all its inhabitants."
"Sad," Jake said, "but she's not exactly wrong."
"She promised to find me a new girl," Finn said, "someone better than her, someone who burn my face off."
"Really," Jake replied, "well that sounds nice."
"I don't know if I can do this again, Jake." Finn sighed.
"Don't worry man, they always say third times the charm," Jake assured, "maybe this third girl will be your charm."
Finn looked up and saw storm clouds in the sky.
"Let's just go home." he said flatly.
Flame Princess remained under the canopy of her house.
"Oh Finn," she sighed, "don't worry, I'll find someone better for you."
She then heard thunder and the sound of raining hitting her canopy.
Flame Princess looked up and saw it raining.
"And I will get on that," she said to herself, "as soon as the rain stops."
So technically this would be like "Incendium" but with Flame Princess taking Jake's role.