Warning: Violence and blood.
It was a normal restaurant; that is, until the owner approached him. A man with round glasses, he introduced himself as Kawahira.
"It's nice to meet you," Tsuna mumbled, bowing and shuffling past him to the door.
"Would you like to see something special about this restaurant?" It sounded weird, but Tsuna accepted anyway – it wasn't like anything was going to happen. He was perfectly ordinary, after all.
"May I ask something?"
Tsuna nodded.
"Are you affialiated with the mafia?"
Tsuna stopped and looked strangely at him. "No?"
"Ah." Kawahira nodded. "Well. Enjoy the room. And remember," he added with a wink, "The number of worlds is infinite." He swung the door open and pushed him through, slamming the door shut behind him. Tsuna glanced around, eyeing the mirrors cautiously. A mirror room, that was it?
He sighed, shoulders drooping. "At least I'm away from those bullies," he said dramatically.
"what bullies?"
"Oh, you know, the usual," he said casually, then paused. "Wait, who-"
He was looking at himself, but at the same, not quite. Tsuna – the other Tsuna, in the mirror, looked down at his gloved hands. "X is for ten, which is Decimo."
"What?" Tsuna frowned. "...Decimo?" He tried out the word, garbling it. The other him laughed. "Gokudera calls you 'Juudaime', actually."
"...Who? That's a weird name."
The other him laughed again, this time more sadly. "Your right hand man. But you don't know him?"
Tsuna shook his head. "No."
"Yamamoto?"
Tsuna thought for a moment. "You mean the baseball ace?"
"Yeah. Has he broken his arm?"
"No...? We've never talked either."
"Huh." His other self examined him. "So different. You look...unhealthy." Tsuna glanced down at himself, at the skinny frame marked with bruises.
"Yeah, well...people aren't exactly nice."
"I never had it that bad," the other him murmured. "I was lucky. But then again, my father cared." He stared straight through the glass, and Tsuna flinched away. "He cared so much," he spat out. "Like hell he does. He's worthless, and you must stay away, okay?" The other him smiled cruelly. "The best way to do that is to die. Jump off a cliff-"
"Don't listen to him," another voice shouted. "Tsuna," and the real Tsuna approached another mirror, ignoring the hissing from the first.
He looked almost the same, except for his mitts and the '27' in red. "Hey," he said easily. "I'm Tsuna. Like you, I guess." He laughed nervously. "Oh, man, this is weird."
Tsuna looked at the second strangely. "Um...?"
"I'm sorry about those," the second said gesturing. "And – I don't know if, anyone's the same..." He looked depressed for a moment, before perking up. "But life will get better, you'll see!"
"Who are you?" The question popped out of Tsuna's mouth. "You're crazy. You all are."
"Hmph. Stupid little brat-"
"Don't call me stupid-"
"Calm down," the second said frantically. "Don't fight."
"Oh, shut up, you-"
"Don't tell me to shut up when you're invading my world-"
The second sighed. "I can't believe this. My life is a wreck."
"Um, excuse me?" A tentative female voice said, and all three froze. The original Tsuna – for lack of a better word – twisted around and gaped at the girl in the mirror. "My name is Tsuruhime...who are you?"
She ducked her head timidly. "I'm Tsuna," all three chimed in. "And you're a girl," the first said stupidly, flushing.
The original Tsuna shot him a withering look. "You nerd. That's disgusting."
"Hey! I can-"
"Please stop fighting," the girl said, and all three boys shut their mouths. "I'm sorry," she said anxiously, "but this man lead me here, and there's mirror-"
"Same," all three chimed in. The second copy leaned back, and called out, "Gokudera, don't damage the property!"
He looked back apologetically. "Sorry. He's my friend."
"Gokudera's a little shit, more like," the first copy grumbled. "So fuckin' annoying."
The second blinked in surprise.
"Gokudera is nice," the girl said defensively, straightening.
"who the fuck is Gokudera?" The orignal snapped in irritation, then paused. "Um, I don't know much about this mirror thing..."
"Yes?" The first asked. The second only tilted his head.
"But, well, the guy, Kawahira, he said the number of worlds is infinite." It clicked for the others, who each examined their rooms and the mirrors inside. "I don't see any others," Tsuna said after a moment.
The first copy's eyes flashed black, the whites disappearing. "I'm not anywhere else, either."
"None here," the girl said.
The second mutely shook his head, pale. "I see tombstones."
"Static," the original whimpered.
"Black," the first observed coldly, eyes still...abnormal.
The girl only covered her mouth. "I see flames? But..."
"Huh?" The original asked, but the other two flattened themselves against the glass.
"On his forehead?" The second said urgently.
"Hands," the first snapped out.
The girl shook her head. "Around, in the air. Like will-o'-the-whisps."
They all exchanged looks. "I don't understand, but he's dying. The world, it's..." she shook her head. "Destroyed."
Tsuna frowned, not really understanding.
"...I don't see anything," the first suddenly panicked. "I can't see-" and a knife impaled his knee, barbed wire dragging him up by the neck. He gagged as blood poured out, the other three both helpless and frozen with shock.
"Damn, you," he gurgled out, his body swinging against the mirror and the glass cracking. Tsuna jolted back as the cracks showed on his side too. The first's hand slammed against the glass, then pointed upwards, before his whole body sagged.
Blood was trickling down the glass, but none of them could smell it. The first to recover was the girl, who said, "who killed him?"
A helpless shrug from the others, all three ashen.
The girl's mirror went blank, and the last thing they heard was a scream.
The second copy and Tsuna looked at each other with panic in their eyes. "I'm going to die," the original whispered, legs collapsing. "I can feel it, oh god, Tsuna, I'm going to die."
The second copy, the other him, crouched and said, "I'm sorry, I don't know how to help you."
The original gave a shaky smile, before the click of the door made him twist around. "Ah," a white-haired man said, stuffing marshmallows into his mouth. He threw a sheet of fabric so the only person left to witness could no longer see what was going to happen.
The man smiled. "My name is Byakuran, and I'm sorry to do this to you." He reached into his coat and drew out a knife. "But better late than never, hmm? I'm a busy man, and you're too powerful to let live."
The last thing Tsunayoshi Sawada saw was the knife piercing his heart, and blood spilling everywhere.
Tsuna, in this, is completely non-mafia. He has no knowledge of Flames, and doesn't know any of the mafia people.
Prompt: 'au where there is a restaurant in namimori where when you go in there you can see the you's of different timelines (you know the things that byakuran can switch between? i forgot what they were called.) but you can't talk to them, you can just see them. the restaurant belongs to kawahira' [Noodle/Freebird]
As you can see, I shook things up a bit.
The first copy = a Tsuna from the AU where he's a merman. Titled: Never Leave the Island
The second copy = is the actual canon Tsuna (I tried)
The third one = another one from my AU, titled Only You Can (You Are The Boss)
It was probably confusing, so sorry~!