Hi. This is Finnceline smut/lemon; whatever you want to call it, it gets kinky. You've been warned.
Wood
Despite hitting 16 and 17 being just around the corner, Finn the Human YOOOUUNG MAN (as Jake liked to say in a deep bass to embarrass his brother) still found himself quite awful with the ladies.
He and Flame Princess had ridden out their relationship as long as they could, before realizing the lack of physicality was grating on both of them. Their separation had been mutual and very cordial (rare for Flame Elementals), and they were still close friends.
Finn still existed in the dreaded realm of the friend-zone with Princess Bubblegum, constantly unaware of where he actually stood. Sometimes he was convinced she was going to push forward and accept his old invitation for a relationship, his maturation and subsequent greater understanding of innuendo confirming his long held suspicions that she directed some loaded flirtation his way.
But Glob forbid HE was the one to initiate anything. And while she had finally stopped calling him "Too young" or (man he hated this one) "Silly boy", he could see in her eyes that she didn't think of him as an adult.
And then, there was Marceline. His recent realizations regarding things of a more crass nature were mostly the result of the Vampire Queen's complete willingness to raze him with all sorts of dirty wordplay.
At points she would simply go on for an hour asking him if he knew what dirty word after dirty word meant, and then gleefully explaining any if he replied no (had he really needed to know what smegma was? Really?). It wasn't that Finn wasn't grateful on some level for the info, as no one else seemed interested in treating him like he was growing up, but sometimes she just pushed things too far.
Not in terms of explaining dirty slang or twisting every situation into a sex-joke, but PHYSICALLY too far. Or… uh… well, not that he didn't enjoy it, but further than friends were supposed to go.
For the life of him, he really couldn't pinpoint exactly when Marceline had begun to sprinkle him with kisses, and palm his chest playfully from behind, and whisper lewd things in his ear before then biting it. But they were certainly in the full swing of it now.
Sometimes he wondered whether or not she had been up for a more physical friendship from the beginning, as looking back the day she had tricked him into being her henchman there had been some SERIOUS dominatrix vibes. Perhaps the Vampire had, rightly so, not wanted to engage with him while he was stuck on Bubblegum. And she hadn't had much of a chance after he got over the pink girl, considering how quickly he was thrusted into his relationship with Flame Princess.
Regardless, she was taking full advantage of him now. And it was weird for him; she was definitely beautiful, but there relationship had been completely platonic until one night when he was 15, and she had broken his conversation by beginning to eat his face off. And she hadn't even mentioned a relationship, or anything of the sort.
Finn didn't know how he felt, really. He definitely was mad fond of Marcy, and found with every passing encounter this fondness grew. The hero could never really convince himself that the day they had met she had kicked him out of his house. Her devilish, fang-laced smile awakened some kind of thrill in him whenever he saw it, and whenever her cool skin drifted close to his, he felt himself grow nervous and all tingly.
But Marceline had given her dad the silent treatment for a few centuries for eating her fries, and Finn was definitely able to make stupider decisions than that. Liable to, even.
Jake kept telling him to go for it, but while Finn realized it might not necessarily be a bad thing if she was, he wondered if Marceline wasn't someone who didn't want to settle down, and liked going through different partners. Then again, she had been on him for about a year and a half.
With a small shrug, Finn figured he should stop clogging his head with thoughts about girls and get his day going. The young man had simply been sitting in his sleeping bag cocoon, waiting for a good reason to plop out of his bed.
As he crawled out of his comf sheets, he noticed with some slight self-embarrassment that he was quite erect. Laughing it off as morning wood while thoughts of Marceline lingered in his head, he quickly made his way towards the shower.
While lost in a paradise of bubbles and warm scrubbing, at one he point paused, sure he had heard something. But, no other noise sounded, and so he began his shower-singing anew. By the time he had finished and was groping for the towel he had left on the rack, the noise was far from his mind.
It was precisely then that Finn realized he could not find his towel. After more blind searching with his hand, he got out of the bathtub to look for it, only to feel two hands grip his arms from underneath and carry him out of his bathroom.
Before he could even begin sputtering confusedly he was lying back-down on his bed, staring up at none other than the Queen of Vampire's herself, who was studying his nude form with intrigue.
"Well, you certainly weren't taking a cold shower," Marceline said with a giggle and impish smile, breaking the silence and making Finn realize he was soaking wet and legitimately wearing no clothing. His mouth dropped open, and after two seconds of complete brain delay he reached to the left of him and pulled his sheets over himself.
Marceline simply floated with a smirk, her cheeks just tinged red. "Go ahead and dress, Finn," She said airily, as if she hadn't just eye-groped his boingloings. "And then we can eat. Oh, and before I forget, Happy Birthday!"
Finn gasped as he realized it was indeed his birthday, having completely forgotten that fact in the early beginnings of the morning.
"Need to give you your present, too," Marceline purred dangerously, tilting her face more toward the floor and batting her eyebrows, her hollow pupils having trapped his own. Before he could object or sputter foolishly, her countenance was a smile that gave little damns about repercussions, and both her hands were pulling at the strings of her red shirt.
After they were fully off, her fingers began peeling the rest of the garnment downward, her cleavage becoming more pronounced with every inch. Her face made it clear she was enjoying this beyond words, until suddenly she was gone, having turned invisible at the last moment. Finn half groaned and half sighed, until his mouth suddenly became very occupied.
A long, ridged tongue seemed to curve through his entire mouth at once, and he vaguely felt two plush mounds pressed onto his bare chest. And then there was nothing but the sound of his door closing, and his heart beating rapidly.
After processing the sheer amount of muck in his brain, Finn nearly fainted when the conclusion was he and Marcy had just done chesties. Her boobs had just been all over him, and based off of feel alone he would describe them as heavenly orbs.
Finn blushed, opting to get dressed before the Vampire came back for more.
"So, 17?" She teased the moment he walked into the kitchen, already feasting on everything red the fridge possessed. On her plate were strawberry's, a slice of red velvet cake, licorice, and Finn swore that a gray ball located suspiciously near her reminded him of a red one they often kept in this room.
"I don't feel it," Finn replied honestly, looking himself over as he made his way to the fridge. Indeed, he wore the same outfit, and while his upper body was much more mature and filled out, some remnants of baby-fat still remained.
"Mmm, but you kind of look it, babe," Marceline replied, her voice silk to his ears. Finn spent extra long in the fridge, trying to calm his raging genitalia and deciding whether or not that was what she had been referring to.
"Umm… was that my present, just now?" He asked nervously as he sat down with a sausage breakfast sandwich. He noticed the innuendo involved the moment before he took a bite, and judging by her axe-like smile so did his companion, but she held off on busting his chops for once.
"Nah, there's more in store," Marceline teased, plucking a strawberry off her plate with her tongue immediately after. Just the sight was so filled with visceral sexuality that Finn could barely take it, squirming in his seat.
"…Like?" Finn asked hesitantly, and Marceline, with an evil smile, flicked one of her shirt strings off her shoulder. Finn did not question further.
"Well, I have a gift for you, but I need your help making it," She replied with a shrug, and now he could see she was purposefully being vague. "You'll like it." The last words were said with so much good intention he had no doubt she was telling the truth. Marceline even gave him one of her smiles where her longest teeth just escape her lips.
"Okay, that sounds good. I hadn't planned much for today, actually," Finn replied, about halfway through his meal.
"Want to fly there in a bit?" She asked, and he nodded enthusiastically. Soon enough they were both full, and exited the Tree-Fort.
However, rather than grab his hand as usual, Marceline looped her arms under his armpits and lifted him up. Her snicker at his squeak of surprise was well deserved as it was quite the squeak, but then without another word they were off.
For the first half of the journey, Marceline was pretty casual for a change, her only romantic interjection being a quick grab of both of his nipples and commenting on how pointed they were from the cold winds.
It wasn't until they were just over the Candy Kingdom that she started to fool around, and being hundreds of feet up in the sky, Finn really didn't have many means of resistance. "Clever girl," He deadpanned as she suddenly shifted so her back was facing the ground, and then adjusted so they were face to face a second later.
"I guess this is another small gift," Marceline said after they had stared into each other's eye for a minute or so, Finn waiting for her to make whatever move she would, and Marceline seemingly content with just looking. Seemingly.
Her lips began to nip into Finn's own, and nipping led to kissing, then kissing to a smorgasbord of tongue. Per usual, Finn was slow to take advantage of the opportunity in front of him, and it was only after a lengthy rub of Marceline's hips against his own that his hands started to explore the body in front of him.
He didn't know how the Vampire knew exactly how to work him, or how badly he wanted her to despite his awkwardness, but was thankful she did. Satisfied humming even came from her busy throat as they fell deeper and deeper into each other, perhaps a result of Finn beginning to smooth her love-handles.
Every once in awhile he would open his eyes and take in the view surrounding them, and though the idea of romance in the sky was wonderful, today there was a plethora of gray clouds rather than any blue (which was preferable, as if the sun had been out they wouldn't have been flying in the first place), but even if it had been a beautiful day out he doubted he would be looking away much from the gray face in front of him. For a moment, her eyes fluttered open, and their fondling, gasping, and movement stopped.
Then Marceline's hand whipped through the air like a Greek javelin and smacked Finn's butt so violently he immediately brought his hips forward, rubbing his crotch right up against Marcy's own. He blushed ecstatically at the sensation, and even the Vampire Queen found herself momentarily stunned.
And then, for once, Finn was the instigator, stealing a kiss from her lips before she realized what he had done and forcibly took it back. They continued on like that for a long while, Finn fighting off lack of breath and questions of whether or not Marceline knew where they were going considering she was flying backwards.
Eventually he realized they were slowly drifting into a tree line, and sure enough eventually Marceline's kisses faded, and they airily dropped down through the trees and onto the ground.
They were in a small clearing occupied by a large oak tree with branches that seemed to spiral into the canopy. As Finn looked around, it became clear to him that Marceline had somehow cleared out a lot of the other foliage nearby; even the grass appeared to be cut.
"You like it Finn?" Marceline says in sing song, the hero becoming aware that the Vampire hadn't let go of him and seemed to have no plans of doing so in the immediate future. With sheer will she pressed him against a tree, and then with a devious smirk protruded several tentacles from his body that quickly wrapped around him, holding him in place.
Finn immediately gulped, realizing this was just like the creepy cartoons about the girls with the monsters with all the tentacles… groping that he had accidentally seen Jake and Lady watching, and he was terrified Marceline was going there. Thankfully she actually wasn't and soon after he was secure she simply gripped his shaft through his pants and rubbed her hand on his jeans.
The sensations that took hold were exotic and exciting, his palms and back sweating as Marceline now began to rub her chest against his still jeaned crotch. Without a word she began to undo his pants, thinking better of it midway through and simply ripping them apart; he had like a thousand pairs, it would be fine. He whimpered and she giggled, pressing her mouth against his easily, and working her tongue inside it while her hand once again began to pleasure him.
This time the hero let the Vampire complete her demonstration of affection, and by the time she ceased rubbing against him, his penis felt hot and oddly like it wanted to burst.
"If I put you in me now you'll just erupt, and we can't have that… NO idea how our bodies work in terms of possibly having kids. So, we'll be safe," Marceline explained, now gently rubbing her fingers up and down on his head, which felt fucking fantastic. "First, you fill up my mouth with your cream filling while you repay my pussy for when you spied on it, perv (she winked at him as he gasped in horror). And then I show you Tier 15. My present to you, Finncerino," She finished, sinking into the air with ease.
Finn gulped, realizing she was going to take him places he still had no clue about and that he was still rock hard and immensely turned on. He gave it his best as Marceline coiled her tongue around his cock and tightened and relaxed a dozen times, drawing out deep moans form the young man, or when she finally began to bob down upon his sex with her lips, suckling like a bear sipping honey, every movement either laced with the crescendo of a slurp of the thick accent of a smack.
Finn, for what it was worth, did his absolute best to keep up, licking at her beautiful, plump folds with the endurance of a wolverine, sucking down as much of her juice as he could. She would shudder just as often as he, but soon the more experienced lover corralled her pray.
It only took her taking him deep in her throat to draw out his first female-induced cumshot, Marceline swallowing satisfactorily as she noted Finn's wanker drool somehow tasted like strawberry ice-cream. His fingers had curled into her thick, midnight hair when he had released himself, his knees trembling as she stared with lust into his boyish face. Glob, she was going to eat him alive, and he wanted it badly.
The Queen of Vampires took her time re-coaxing his vigor, teasing his head with silky strides of her tongue or gentle nibbles, and occasionally slaps directed at his chubby butt that made him quite embarrassed, and seemed to extend his erection.
Finally, she smirked in a satisfied manner, pulling his shirt off but directing him to keep the hat, and then pulled off her shirt, forced Finn to remove her bra, and slipped off her red leather pants, which she had apparently had be goin' commando in.
Finn felt another flux of erotic prowess as the Queen rubbed her dainty, seemingly sculpted lips upon his length, teasing him with only one more smile before arching her hips back and piercing herself upon his penis.
The hero's hips shot forward in basic instinct at her motion, Marceline moaning as he entered her so powerfully. Bonnie NEVER fucked her this hard with the candy-cane strap-on. "Oh, plow me Finn," She whispered, her focus on dominating him lost in her own urges, and her tight pit loosening more with every thrust and beginning to leak like a crumbling dam.
"Ho-LY FL-UB, M-ARCELINE!" Finn shouted, his words broken as he lost his mind in sex. "You're… so good… I want you…" He begged, plugging her hole faster than anyone else ever had in her 974 years of sexual activity.
Marceline bit into his neck to avoid screaming in her orgasm, the violent, minute long vibration from her Vampire strength leaving Finn's dick pumping her stomach full and supple with his juice, her worry of pregnancy gone. "Ahhhhhh…." She murmured, spinning his dick in small circles with revolutions of her own hips, and loving the sensation. "More, Finny. I'm loving how much of a horny berserker you are."
"Oh, damn… Queen…" He whispered in delight as she pulled him out, and then pressed him somewhere much narrower and tighter.
"And B-Bonnie, n-never DOES this," Marceline huffed as Finn realized with wide eyes that he was in the girl's butt, and that it felt fantabulous.
"M-Marcy, what is this called?" He asked, flabbergasted.
She laughed and replied, "Anal, baby. I love how hard you get for me." Her lips silenced any retort he could have made and explored his face again, but now her tongue snaked down his body and began to wrap his testicles in tight bonds, pulsing as to squeeze them lightly.
Finn groaned in amazement at the sensation, but this time held his load for five more minutes. Then, as Marceline arched her back and screeched out like a true creature of the night, he exploded with her, reveling in every thrust into her tight, convulsing ass. It felt heavenly, and after he pulled out, he still seemed to drip for minutes, and he was embarrassed to find a pool of his gunk collecting below them.
"Oh glob… Marceline, I love you," He whispered, freezing a second later at this statement and as she considered him.
"…R-Really?" She asked, surprised, and blushing unsurely as she rubbed her arm.
"Y-Yeah," Finn admitted, glancing downwards. "You're always so fun, and calming, and are so good at putting people in a welcomed mood. And you're a Tier 15 goddess," He joked, his dick pulsing again at his words. "I… I want to be with you. Is that okay?"
Marceline smiled widely, kissing his forehead and then snuggling into his side. "It's your birthday, Finn. You can have anything you want. How does round two sound?" Her leg bent out and her foot came up, grasping on his now shrinking manhood.
When she squeezed tightly, the hero panted, his hand flying down to her vagina and witnessing first-hand the mess he had made, lulling her into mounting him again. They went on for another hour until Marceline simply dropped them from the tree, and they landed in each other's arms, butt-naked in a forest, covered in each other's genital cocktail and dreaming about humping each other's brains out.
The new Treefort's construction was delayed for another day, and no harm was done. Unsurprisingly, the Vampire and the hero went on to have a very successful, and physically excessive, relationship.
I can't get it out of my headcannon that after Finn reaches a certain age Marceline just turns him into her personalized sexual deviant. I have no idea what else to say, so thank you for reading.