#fandom fusions

Two quiet pairs of footsteps could be heard filling the echoey hallway. Locked steel doors and pure white walls filled the hallway they walked in. The two beings that filled this hallway with their footsteps, felt very out of place in this kind of environment. They couldn’t describe the feeling of overwhelming curiosity mixed with the unbelievable sense of doom. This collective of emotions made the two people wary and cautious as they walked. Slowly, their eyes gazed upon the countless number groups on the doors. 

“M-Mario…I don’t like this…” One of the men told the other. 

“We’re really close. We just need to find the right door.” The other man said. 

“What if…I don’t like it?” The man dressed in green, had asked. 

“Don’t worry, Luigi. You will like this one. I’m sure of it.” The man named Mario, had told the man in green. 

Luigi walked to the door at the end of the hallway, and looked at Mario. “It’s the 999 number, right?” he asked. 

Mario looked at the paper in his hand, and nodded his head. “Yup. SCP-999.” Mario told him. 

Luigi bit his lip and looked through the windows of the chamber. “Hmm…” He looked inside the windows, and saw the glob of orange that was hopping around the containment chamber. “Is…is that it?” Luigi asked. 

Mario looked through the window and smiled. “That’s 999. Isn’t he cute?” Mario asked him. 

“He’s...I don’t know…” Luigi muttered aloud. “He’s strange-looking, but…” Luigi widened his eyes as he saw the creature getting closer. Luigi widened his eyes as he saw it slide its way closer to the window. Luigi stared at the creature with newfound awe and wonder, as 999 blubbered and ‘bounced around’ with its body. 

Mario smiled and pulled out the key card they had been given. He slid the card down, and watched as the red light turned green as it made a clicking sound. Mario pulled on the door, opening it and looking at Luigi. “You ready?” Mario asked. 

Luigi nodded with a smile as he got up and away from the window. “Ready as I’ll ever be.” he replied. 

Mario pulled the door open a slight bit more, and gasped as he saw 999 just waiting for the boys to enter. Mario entered first, and kept the door open for his brother. Luigi moved through the door as well, and took a moment to hear the door close behind him. “Okay…” Luigi looked over at SCP-999 and waved at it. “Hello.” Luigi greeted awkwardly, unsure what else to say. 

Mario knelt down. “Hi 999. I’m Mario.” He greeted. “And this is Luigi.” He told 999, hugging Luigi close to him. “He’s my brother.” Mario told it. 

Right away, Mario could smell something rather comforting from their childhood. 

“M-Mario?” Luigi looked at his brother. “Is…is it normal for 999 to make you feel…excited?” Luigi asked as he felt giggles bubbling up in his lungs. Mario giggled. “Do you smell Papa’s waffles?” He asked. 

Luigi nodded. “Y-Yeah…I don’t know how, but…I do.” Luigi admitted. 

Mario chuckled. “999 can emit familiar smells to make you feel euphoric and nostalgic.” he explained. 

SCP-999 let out some gurgling sounds as it made two pseudopods appear from its body. The first pseudopod touched Mario’s cheek, making Mario widen his eyes and smile as he cooed in emotional happiness. The second pseudopod was going to touch Luigi, but decided to wait patiently for its turn. 

Luigi was confused by Mario’s reaction at first. Mario only acts like that around babies and puppies. And this creature was not even close to a puppy. “M…Mario-” Luigi tried not to laugh at him as he saw Mario blushing and smiling widely. He looked like an elated toddler. “Are you okay?” Luigi asked, covering his mouth slightly as he chuckled. 

Mario let out a fit of giggly laughter. “Ihihi probably look so stupid right now…” Mario mentioned, making Luigi laugh as well. “Buhut…I don’t care. I feel amazing.” He admitted. 

Luigi looked at 999 and saw the pseudopod just sitting there. Seeing how Mario was reacting, Luigi reached out for the pseudopod. “May I?” He asked politely. When the second pseudopod reached up and touched Luigi’s hand, Luigi widened his eyes and looked at 999 with shock and…growing euphoria of his own. “W-Wow…” Luigi reacted, feeling a toothy smile growing on his lips. He laughed a bit as he felt the SCP’s strange texture. It threw him off guard at first…It felt like orange peanut butter! But the curiosity seemed to trickle out of his mind the longer he held 999’s pseudopod. “Hehehe…Ihis this what you were-” 

Mario nodded. “Uh huh. How do you feel?” Mario asked his brother with a giggle. 

“Ihi…I get it now…” Luigi muttered, hanging his head and giggling. “I feel great!” 

Mario bursted out laughing at Luigi’s face. “Ihit’s like you were just told we were going to Disney world again…” Mario mentioned with a laugh. 

Luigi chuckled and scratched the back of his head. “Y-Yeah…” 

999 looked towards Mario, and slid its body onto Mario, engulfing him in the peanut-butter substance. Mario gasped and froze in shock. The substance felt cold, yet…comforting. And his body felt wet, but dry all at once. It was…really strange. 

“Is…is he hugging you?” Luigi asked, both nervous, but also calm at the same time. This creature was making him feel so many emotions at once, that he couldn’t even think straight anymore. 

Mario smiled a bit. “It…feels like water, but...thicker.” Mario admitted. “Ihit’s weihihird-” Mario jumped and jolted as giggles and laughter left his mouth. “Wahahait, whahat are you dohohoihihing- eeEEK!” Mario squeaked before leaning his head back as he fell into a fit of laughter. “HAHAHAhahaha!” Mario laughed, wiggling around somewhat roughly and kicking his feet inside 999’s translucent body. 

Luigi stared at Mario, beyond confused. “What is…I don’t get it.” Luigi told him. 

“Ihihit tihickles- Ihihihit TIHICKLEHEHES-! AAAHAHAhahahaha!” Mario laughed somewhat heavily, wiggling around a little harder. 

Luigi had to cover his mouth to prevent from laughing. There was no way…How could it be tickling Mario from inside its body?! And how was Mario so…calm about it?! Usually Mario was a wiggly tickler. So you’d have to be really strong and ready to dodge if you were going to tickle him and come out unscathed. But Mario looked…almost powerless to 999’s gelatin-like body. It was so strange and yet…it looked really fun. 

“Ihihihi cahahan’t stohohop ihihihihit!” Mario reacted, opening his left eye as he removed his hand from 999’s body and covered up his own wobbly grin. 

Luigi couldn’t stop himself from laughing alongside him. The creature was making them act almost drunk without even a sip of alcohol! He had no idea why, but seeing his brother like this was making him lose his mind with laughter. It was absolutely hilarious, and he couldn’t quite explain why! Luigi soon sat himself up and let out a cheer. “Woooo! God, this is awesome!” Luigi reacted. 

“Ohokahay, ohohokahahay- Thahat’s enough plehehehease-!” Mario begged, fighting a little harder. “Ihihit’s toohohoohohoo muhuhuch!” Mario admitted. “Gehehet Luihihigihihi!” Mario said next. 

Luigi widened his eyes. “Wait, what?! Hey!” Luigi reacted. 

999 seemed to understand his request, and gently let Mario go by sliding his body out from its body. When Mario was let go, he had hugged himself with his arms and kicked his feet a little bit to combat the leftover tickles that still plagued him. It also didn’t help that he had developed butterflies in his stomach, which had ALSO begun tickling him from inside. 

“You okay?” Luigi asked, not entirely used to seeing Mario so overwhelmingly happy. 

“Hahahaha- Hahaha- Yohohou gohotta try ihihit!” Mario told him. 

Luigi was about to give him a reply, but was interrupted by the feeling of a cold substance filling his back, before surrounding his front all the way up to his shoulders. “Whoa-!” Luigi reacted, looking down as his body was covered in orange. “Uuuuh…” Luigi looked behind him slightly, and saw 999’s ‘face’ looking at him. “Hi?” He said, giggling a little bit. 

999 gurgled happily and nuzzled its ‘face’ into the back of Luigi’s head for a few moments, earning a few giggles from Luigi. He enjoyed the nuzzles for a bit, before feeling gentle, tickly vibrations against the back of his neck. “eeEEHEHEHEEEK!” Luigi laughed, attempting to lean his head back to stop the tickles. But 999 couldn’t be squished down! All he could do was laugh! “Wahahait-!” Luigi gasped and started wiggling around as more tickly vibrations filled his body. “WAHAHAhahaha! Ihihihit’s sohohohoho weihihihihird!” Luigi giggled. 

“I know, right!? It feels like back massagers against your ticklish spots.” Mario reacted. 

999 gurgled and cooed as it tickled everywhere it could reach. It was strange being tickled by such an unusual creature. Any other time, Luigi would probably be surprised and fighting to get out. But…999’s euphoric effect was making him all giddy. This made the tickle attack feel more…fun than anything else! 

“Do you need it to stop?” Mario asked. 

Luigi tensed up and squeezed his arms against his sides. “Nohohot yehehehet- GAHAHAHAHAA! NOT THERE- NOHOHOT THEHEHEHERE!” Luigi cackled, his wiggles almost doubling. 

Mario chuckled and patted Lu’s left shoulder which was poking out of 999’s body. “If you need it to stop, let me know.” Mario told him. 

Luigi squeaked and squealed, unable to stop his jolts and kicks. “OHOHOKAHAHAY, EHEHENOUHUGH PLEHEHEASE!” Luigi begged, his hat falling off his head when he threw his head back. 

Mario picked up the green hat and looked at 999. “He wants you to stop.” Mario told him. 

With a few gurgles in response, 999 calmed itself down and went still. Luigi’s cackles and laughter slowly began to calm down. Luigi leaned his head back and let out breaths of relief and exhaustion. “Ihi…Gosh…” Luigi looked at the top of 999. “How did you know my worst spot?” Luigi asked. 

999 nuzzled into Luigi’s face with a sense of worry in its gurgle. It was almost like 999 was trying to ask if he was okay, and if it went too far. But Luigi was quick to reassure 999. 

“Don’t worry. I’m okay. You’re in the clear.” Luigi told it. “It was kinda fun, actually…” Luigi bit his lip. “But then 999 found my shoulder blades…” He admitted with a chuckle. 

Mario chuckled and traced a finger against his brother’s upper back. “You always were sensitive there…” He admitted. 

Luigi jolted and arched his back, letting out surprised squeaks quickly followed up by laughter. “Mahahariohoho whyhyhyhy?!” Luigi asked. 

“Cause it’s funny!” Mario admitted. 

“Ihihis nohohot!” Luigi argued, turning himself around so his shoulder blades weren’t so exposed. Mario chuckled and stopped going for it. “Alright alright, I’m done.” Mario told him. “Hug?” He offered. 

Luigi smiled genuinely and wrapped his arms around him. Though he was slightly nervous Mario would go for the really bad spot, He trusted his brother more than anyone else in the world. And nothing was going to change that, not even Mario. 

…Or so he believed…

A feeling of shock mixed with betrayal had taken over his mind as giggles erupted out of his lungs. “Wa-wahahahait- Mahariohoho whahat ahahare yohou-” Luigi hid his face against his brother’s shoulder and laughed into it. “Cohohome ohohohohohon!” Luigi reacted. 

“Listen, this is completely your fault! I’m surprised you trusted me so freely!” Mario reacted. 

Luigi wrapped his arms a little more around Mario and started tickling everywhere on his sides that he could reach. “Cahahan’t tihickle mehehehe ahand thehehen expehehect nohohothing bahahack.” Luigi warned. 

Mario jumped and cackled, wiggling around and struggling to get out of his grip. “eeEEHEHEEEEK! NAHAHAhahahaha! Letmego! Lehet mehehe gohohoho!” Mario giggled helplessly. “Whehehehen dihihid yohohou behecome so plahahahayfuhul?!” Mario asked. 

Luigi chuckled. “Since meeting 999! Speaking of: Are you enjoying this?” Luigi asked, looking at 999 with a smirk on his face. 

999 gurgled and bobbed the top of its body up and down, similarly to a person nodding their head. 

Luigi laughed a bit and turned his brother around so Mario’s back was against his chest. “How about a little bit of this?” Luigi squeezed and skittered his fingers on his sides. 

Mario squeaked and threw his head back, cackling hysterically. “OHOHO NAHAHAHAHA! LUIHIHIGIHIHI IHIHIHI’M GOHOHONNA DIHIHIIIHEEHEHEHEEHEEE!” Mario yelled at him. “Oh, you’re gonna die?” Luigi asked with a smirk. “Tell me: Would you rather die by my hands? Or by 999’s paws?” Luigi asked. 

Mario hung his head and giggled, wiggling and moving around. “IHIHI DOHOHON’T KNOHOHOHOW!” Mario told him. 

“Hmmm…Well, I guess it’s either you’re tickled by your brother who’s known you for ages, or you’re tickled by the living embodiment of the tickle monster.” Luigi teased. “And I agree…that’s a hard choice to make.” Luigi teased. 

Mario struggled and wiggled in his arms, unable to stop the endless laughter that left his mouth. It was almost overwhelming how ticklish Luigi’s fingers were capable of being. And it embarrassed him more when he realized how powerless he was compared to his brother. Which, as an older brother, is pretty embarrassing. 

“PLEHEHEHEASE STOHOHOHOP. IHIHIT’S TOOHOO TICKLIHIHIHISH.” Mario pleaded. 

Luigi smirked and looked at 999. “Is it time to stop?” He asked. 

999 slid up to Mario and touched his cheek with its pseudopod before gurgling and cooing. “Awww, 999’s giving you love too.” Luigi teased. 

Mario giggled and curled his neck in as the pseudopod moved itself under Mario’s cheek towards his jawline. Mario’s laughter had died down a little bit while Luigi had been momentarily distracted, allowing Mario to breathe a bit. “Ihihi feeheeheeheel ihihit.” Mario admitted. “Ihihihi feeheeheeheel thehe love.” Mario further explained. 

Luigi looked at 999 as he stopped his fingers altogether, and switched to hugging Mario from behind. “I love you, Mario.” Luigi said, resting his chin on Mario’s shoulder. Mario placed his hand on the side of Luigi’s face, and patted it softly. “Ihi thihihink the euphohohoria is gehetting to be too muhuhuhuch fohor you.” Mario admitted. “Wehehe should leheave.” Mario told him. 

Luigi sighed and smiled softly, nodding his head. “Okay.” He replied. 

He put Mario down and picked up his hat, putting it back on. “Thanks for grabbing my hat.” Luigi told him. 

“No problem.” Mario replied. 

“You ready to go?” Luigi asked. 

Mario nodded and gave 999 one more hug. “Bye 999.” 

999 nuzzled its face into Mario’s cheek…

Luigi watched their interaction excitedly, and giggled as 999 engulfed Mario in its body again. He even laughed as Mario swam around inside 999. He even swam up to the wall of 999, and knocked on the gelatin, waving and smiling at Luigi. Luigi waved back at him, noting the occasional bubbles that would form and rise above Mario. 

Mario reached out of 999’s body, and pulled Luigi into its body with him. Now both the brothers were swimming inside 999! Though they knew they should’ve been leaving, Luigi didn’t care. A couple more minutes with 999 never hurt anybody. He noticed the bubbles forming on his hand, and rising up above his head. He thought it was very cool, and almost pretty. Looking up, he watched as the bubbles rose up, until they popped…only to be followed up by a couple more bubbles…and then a few more…And even more…

Luigi looked down, and widened his eyes in horror: his hands were disintegrating! And every bubble that rose up from his hand, was a fragment of his body! Luigi tried to gasp, but coughed and reached for his throat as he realized he couldn’t breathe while engulfed by 999’s body.

With his hands gone and only his lower arms now visible, Luigi tried to crawl himself out of 999’s body. But this proved to be really difficult, especially when he could see himself losing more of his arms. Looking down, Luigi noticed his feet were completely gone…reduced to white ash-like fragments, while only his upper legs remained. He could feel his lungs convulsing and begging for air as he swam helplessly within 999’s body. This euphoric dream had quickly turned into a horrifying nightmare. 

“Luigi!” He looked at his brother, who was almost completely bubbled into white fragments just like him. Mario reached out with his disintegrating hand, and grabbed his right shoulder, which was still intact. “It’s all gonna be okay!” Mario said to him. 

Luigi widened his eyes as he saw his right eye falling apart from the bubbles. “Mario!” He yelled. “Don’t leave me here alone!” He pleaded. 

“I’m right here!” Mario told him, his right hand now disintegrating as well. “It’s only a nightmare!” His brother repeated. 

Luigi could feel his right eye’s vision fading out as it turned to fragments as well. “M-Mario-” 

Luigi jumped and gasped, suddenly feeling the ability to breathe. His vision was blurry, but he could feel his fear melting the moment he registered the flash of red and the comforting arms around him. He wrapped his arms around Mario as tightly as he could, trying to stop himself from crying. “Mario…” Luigi breathed deeply to try and overcome his restlessness. 

“That sounded like quite the nightmare.” Mario reacted. 

Luigi couldn’t stop the laugh that left his mouth. “It wasn’t a nightmare…well, until the end.” Luigi admitted. “The dream turned so quickly, it was hard to understand.” He admitted.

Mario chuckled. “Is that why I heard laughter from you earlier?” Mario asked. 

Luigi widened his eyes and blushed a bit. “I-I-Uh…” He muttered. 

Mario snickered. “I woke up to you giggling in your sleep. And you kept giggling for a little bit.” Mario admitted. 

Luigi covered his face with his hands. How embarrassing…

“I didn’t wanna wake you at first, cause…you sounded like you were having fun.” Mario admitted. 

Luigi uncovered his right eye awkwardly. “Ihihi was…Wehe were visiting a…creature in a laboratory.” Luigi explained. “Someone had come up with a creature locked in a laboratory, with its file written out on this website.” Luigi explained. “The creature, whether you touched it or sat in the same room as it…it would make you euphoric and happy.” Luigi explained. 

“Aw man…That sounds amazing!” Mario reacted. 

“It was…” Luigi chuckled. “The creature is…like a blob of jello. Only, it’s not jello. The stuff it’s made of, is supposed to be peanut butter?” Luigi explained. 

Mario tittered and snorted. “Ohoho?!” He couldn’t stop the cackles and laughter that left his mouth. “Ihihi have no clue what you’re talking about.” He admitted. “It sounds insane…But I love it.” Mario admitted next. 

Luigi bit his lip. “Near the end though…999 had taken both of us, and we were pretty much swimming in its body…” Luigi let out a breath. “You started disintegrating. We both started disintegrating.” Luigi explained. “I couldn’t breathe. I was drowning and falling apart, but you were speaking to me.” Luigi told him. 

“...What did you hear?” Mario asked. 

“It’s gonna be okay…I’m right here…” Luigi muttered. 

Mario raised his eyebrows. “So you could hear me…” Mario muttered. “Good.” He said. “Because when you started gasping for breath and…shifting in your sleep, I didn’t know what to do. I could tell you were scared, because your movements and reactions were getting worse.” Mario explained. 

Luigi shook his head. Luigi hung his head. 

“When you started muttering my name, that’s when I knew you needed to wake up.” Mario explained. 

Luigi pulled his brother into his arms tightly. “Thank you, Mario.” Luigi told him. 

Mario smiled and hugged him back. “Of course.” He replied. “What are brothers for?” 

He felt Luigi’s grip tighten. Mario smiled a bit and gave his brother’s side a little tweak, making Luigi giggle in the process. 

Mario broke the hug and wiped the tears off Luigi’s face. “Alright, no more crying. It was a happy dream, right? About this creature that’s supposed to make you really happy?” Mario asked. 

Luigi chuckled. “Yeheah…” 

“Wanna tell me more about it?” Mario asked. 

Alex Rider (AR) × Harry Potter (HP)

Harry Potter and the Teenage Spy by Rod I don’t know how to describe this other than it is quite literally, when fandoms collide. See what I did there? …Sorry. The first instalment is set during ‘Deathly Hallows’: what if Alex (and Tom and Sabina) was/were in the café the Golden Trio escaped to after the wedding? After this, well, you know how Alex is – can’t leave anything alone, has to see things through no matter what, casually popping in to fuck shit up – no, really, this series is literally just Alex inserting his sassy self into Deathly Hallows. 😅

Of Wands and Stun Darts (And All the Things in Between) by tomaetotomahtoe This series is so sweet and Harry and Alex’s relationship is incredibly tender. The parallels are drawn between them in such a way that highlights the similarities in their personalities without making them carbon copies of each other. They’re so soft with each other – they’re also mutually pining away for each other 🤭. You’ll be giggling over these adorably silly boys.

Miraculous Ladybug (ML) × Avengers

What the Cat Dragged In by Kryal Tbh, I don’t really know what to say for this one other than it’s just… good. The way the world of Miraculous is viewed through the lens of an outside perspective is simply brilliant and the worldbuilding beyond what we see in canon is very clever. Adrien trying to figure out the physics behind the miraculous is just *chef’s kiss*. These two media were skilfully integrated and the characterisation is on point. Lastly, the tags – ‘the Avengers are not immune to cute’, they certainly aren’t! 😂😂😂

Undertale (UT) × Harry Potter (HP)

Under the Veil by poplasia I didn’t even know I needed this friendship until I read it. Sirius and Sans get on like a house on fire, the mechanics behind the magic are cleverly devised, the banter is hilarious and I can’t forget the puns.

Alex Rider (AR) × Artemis Fowl (AF)

Dead Man’s Party by thealphaaxolotl Post-canon strangers to friends to lovers!Alexmis featuring ‘oh my god they were roommates’, with your standard mutual pining as well as lashings of tension and angst.

Fairy Roses by crowprincess14 A short tearjerker as everyone deserves a little tragedy as a treat. It’s not specifically tagged as Alexmis but it’s definitely inferable. There are references to a canonical (but technically temporary) character death if you don’t read that. If you need comfort after this, there is a companion fic written by alexmis with a happy ending.

Alex Rider (AR) × Avengers

MI(6 Degrees of Separation) by mobilisinmobili Imo, anything written by Mobi is great. The source media go really well together and the characterisation feels natural. As always the worldbuilding is very well done, leaving a vivid impression of the gritty underworld espionage and crime both belong to.

Miraculous Ladybug (ML) × Undertale (UT)

Miraculous Tale by awkwardnarturtle This better fits the definition of a fusion than a crossover, honestly. The ML characters are effectively transposed into the world of Undertale without just feeling like an expy and everything comes together so well. Marinette and Chat’s relationship is delightful to read while the little hints of mystery here and there evoke that nostalgic eagerness to discover the game’s secrets.

Puella Magi Madoka Magica (PMMM) × Avengers

Incursio by Mr. Omelette The worldbuilding on the PMMM side has definitely influenced my own headcanons and the characterisation is rather fitting. Also, a family can be one American supersoldier displaced through time and two magical girls displaced across space.

Assassination Classroom (AssClass) × Boku no Hero Academia (BNHA)