Disclaimer: Katekyo Hitman Reborn and Blue Exorcist belong to their respective owners.

Warnings: OOC (really, really OOC; like out of this world character), failed humor, and I don't even know.

"Mwahahaha…puny Vongola guardians," a voice echoed throughout the clearing where five and a half Guardians, their Sky, and the Sun Arcobaleno stood. One of them was missing, but the Vongola were too preoccupied by the apparent threat awaiting them to count heads. Even more than that, tall, flickering walls of blue flames surrounded them, somehow not burning the trees. "You've fallen into my trap."

The voice echoing through Namimori's forest and rustling the leaves was deep and resonant, as though several voices had merged into one. Sawada Tsunayoshi's Hyper Intuition (the same thing that told him he'd left the stove on) was running wild, and he just couldn't shut it up. The brunette was already in Hyper Dying Will mode with gloves and everything, and stood firmly against the disembodied voice along with the others.

"Who are you?" he demanded, tightening a fist. A deep rumble of a laugh answered him, and Sawada Tsunayoshi clenched his teeth.

"You ask who I am?" the voice repeated in amusement. The temperature suddenly escalated to the point that the leaves on the trees disintegrated, and the Vongola felt a heavy and dangerous pressure ram into them from all sides.

"Careful, Tsuna," the Sun Arcobaleno Reborn warned. His gun was out – even his own Spartan tutor's deadly aura couldn't compete with the enemy's for once.

"Who am I?" the voice repeated again, seemingly closer than before. A rustling nearby caught their attention, and all eyes and weapons – flames, flame guns, flame tonfas, tridents, and fists – faced a part of the trees where growling footsteps came from and trees crashed in the distance. "Who am I?"

They tensed in anticipation.

"I am the Lord of Gehenna."

crash…

"I am the ruler of all demons."

Crash…

"I am the user of Blue Flames."

Crash!

"I am—!"

"Getting annoying," Gokudera Hayato muttered under his breath, and the others could only agree silently.

"Gyahahaha! Fine then, boy," the voice said, cackling. A shadow had appeared behind the blue flames, and the Vongola tensed for a battle far worse than any others. "I'll cut to the chase!"

"Get ready, everyone," Tsunayoshi told the others.

"I'm…YOUR WORST NIGHTMARE!"

A small figure leaped through the flames and landed on the opposite side of the clearing of the Vongola.

"Name's Sat—"

"LAMBO!?"/"STUPID COW?!" The shouts coming from the group blasted over the declaration of the person in front of them, whom they'd nearly forgotten all about. It was Lambo, a five-year-old kid wearing a cow-print suit and an afro the same size as his body. But something was very off about him. For starters, his ears, normally hidden by his hair, pointedly poked out of his curly hair. He wore a creepy grin with sharp fangs, and his normally green eyes had turned a blood red. The cow tail attached to his suit flared with bright blue flames.

"Hey! You ruined my introduction!" Lambo, or rather, whoever or whatever possessed him, whined. Then his grin returned. "Anyway, name's Satan. You know, ruler of Gehenna and all that."

"Oya? What are you doing here?" Rokudo Mukuro questioned. He had a knowing look in his eye.

"Long time no see, Mukuro," Lam—no—Satan almost cheerfully acknowledged the indigo pineapple who'd been through the Six Paths before.

"What've you done to Lambo?" demanded Tsunayoshi.

"Ahaha, this kid?" Satan said, gesturing to the boy he was currently in. "So many questions you humans possess. Nothing much. Unless you call taking over the realm of Assiah 'nothing much'! Gyahahahaha!"

"Is that it?" an unimpressed Tsuna asked.

"W-what?" Satan looked at him with a shocked expression. No one, absolutely no one, would ever dare to talk back to him or even dare to look at him. What weirdos were these?

"We've faced trained assassins, a crazy marshmallow freak, undead jailors, and even a centuries-old Earth alien," Gokudera Hayato stated.

"And all of them EXTREMELY wanted to take over the world," said Sasagawa Ryohei.

"How do we know you're even real?" questioned Tsunayoshi.

"He's real alright." Everyone turned to Mukuro, then back at Satan.

"Dang right I am!" the demon cackled. "And I'll crush you like the insects you are with this puny body!" Wait. Puny…body? Satan examined Lambo's body again and seemed to realize for the first time that he was in a five-year-old's body. "WHY AM I IN A FIVE-YEAR-OLD BOY?! GAAHH! I GOT THE WRONG PERSON, AGAIN!"

As the demon began to freak out, Tsunayoshi turned to his Storm Guardian and said, "Gokudera-kun, do your thing."

"Right, Juudaime!" Gokudera Hayato walked to the front of the group fearlessly and stared down at Satan. Juudaime's counting on me now! I can't mess up! he told himself, eyes shining with pride. The others looked on in exasperation at this habit of the bomber.

In a FWASH! Gokudera Hayato swept out a long scroll with ink writing (an ofuda) on it. Raising his other hand as if to strike, he shouted an exorcism spell, "Rin! Pyo! To! Sha! Kai! Chin! Retsu! Zai! Zen!" And with each blow to the air, Satan flinched and clutched his chest where his heart would be…if he even had one.

"Akuryō…Taisan!" With a wide sweep, he threw the paper at the demon, who screeched in pain and fury. And then the paper seemed to merge with Lambo, forcing a small blue flame out of the back of his head that plopped onto the ground. Lambo, eyes closed, rolled over and fell asleep, dreaming peacefully somehow.

All eyes gazed at the strange blue flame that seemed to stare up at them. Then, a mouth of flames appeared.

"I'll be back, Vongola!" Satan's voice came from the fire. "Mark my words! You may have bested me today, but you haven't seen the last of me! Gyahahahaha!"

With that, the blue flames bounded off into the woods, and the flames surrounding them died down. But for the next few moments, they stood in complete silence. The orange flame disappeared from Tsunayoshi's forehead, and he relaxed his muscles from a fight that didn't occur.

"…What just happened?" he wondered aloud. He glanced at the others, who seemed just as bewildered as he was. "Ah! Lambo!"

Ignoring the others' warnings, the Vongola Sky ran to retrieve the sleeping Thunder Guardian. But as he was bending over, Lambo's head turned completely around to face him. It was Satan.

"GYAHAHAHA! I LIED!"

"HIIIIIIIIIIIIIIIIIIIIIIIIIII IIIIIIIIIIIIIIIIIIIIIIIIIIII IIIIIIIIII—

—IIIIIIIIIIIIIIIIIIEEEEEEEEEE EEEEEEEEEEEEEEEEEEE—!"

"Oi, wake up dame-Tsuna!" Reborn slammed his heel into the cheek of his student, who promptly fell out of his bed in a tangle of sheets.

Sitting up quickly, Tsunayoshi fwipped his head around rapidly, searching for any signs of blue flames. When he saw none, he looked at his tutor with a confused expression.

"R-Reborn?" he wondered.

"You were dreaming," Reborn stated. His chameleon Leon then morphed into a green pistol, which he aimed at the brunette. "Now, hurry up, dame-Tsuna, or you'll be late for school."

"Hiiee! I get it! I get it!" Tsunayoshi shouted, waving his arms around wildly. That all must've been a dream, then, he decided, from those stories Yamamoto was telling us about those people. He rushed around his bedroom, nearly tripping over every step. After getting dressed, he took one step out into the hallway when…

"Gyahaha!"

A childish laugh stopped him dead in his laugh. There was no way.

"Ah, Tsuna!" Said brunette flinched and creaked his head downward to look at the boy in the cow-print suit standing below him. Lambo. "Hurry up! Hurry up! Maman's making breakfast!"

With that, the boy then skipped off as though nothing had happened. And maybe nothing had. Sawada Tsunayoshi sighed, shaking his head at how tired he must be from Reborn's Spartan training. He started to follow Lambo downstairs when something filled him with unease.

Sawada Tsunayoshi shook his head again. He was just tired. That had to be it.

After all, those blue flames on Lambo's 'tail' couldn't be real, right?

A/N: I really need to stop trying to be funny, 'cause I'm really not. I wrote this in an hour or so, which is why [I think] it's so bad. And before you ask how can Satan possess someone (especially someone like Lambo), don't ask, because I don't know either. I'm making this up as I go along.

Anyway, thanks for your reviews, faves, and follows, particularly the ones that make me smile. By the way, I'm trying to keep this 'kid-friendly', though that's kind of redundant when one of the characters is Satan...