"Ah...geez...I don't even know which class I'm teaching..."
Tsuna entered the school building; he was lucky that Kyoya wasn't patrolling the area at that time.
The brunet walked up to the school receptionist, running a hand through his gravity-defying hair.
"Ano..."
The school receptionist, a blonde lady, looked up and scoffed, making Tsuna quirk an eyebrow.
"Late again Sawada-Sensei?"
Tsuna tilted his head before giving a sheepish smile to the blonde, surprise the other.
'Is this really the Dame-Sensei?!  He looks...hot!'
The blonde receptionist blushed deeply, turning her head away.
"W-What are you here for?"
Tsuna gave a small chuckle.
"Maa...my Dame brain seems to have forgotten where my room is.  Can you please tell me which classroom I'm in again?"
The receptionist stuttered her answer.
"F-Fifth floor, c-classroom 1E."
Tsuna gave a bright grin before waving goodbye at the other.
"Thanks!"
The brunet left, leaving a flustered blonde behind.
"Seriously..." The blonde pouted, scowling off to the side. "Is someone impersonating Dame-Tsuna?"
~~
Tsuna sighed running his hand through his hair as he entered room 1E, his classroom.  The ex-Decimo didn't expect objects to start flying at him, and it confused the brunet slightly.  He dodged the thrown objects with ease before landing next to his desk, setting his bag and papers down.
Tsuna noted that the objects stopped flying and took his chance to glance around the room, an amused and curious gaze flitting across his face.
"Well...I wouldn't have expected to get greeted by flying objects...oh well."
The class gaped at the brunet, dropping other objects that they were probably going to throw at him.
'Hmmm?  I guess I was a Dame-Sensei...it seems that I'll always be Dame!  Haha!'
Tsuna let a small smile slip to his face as he spoke kindly to them, a small smirk forming on his face.
'It seems that I'm in charge of a bunch of delinquents...amusing.' "Now~take a seat my wonderful students."
Most shivered and immediately sat down, including the Vongola group--excluding Kyoya, Chrome and Mukuro, who weren't there--that Tsuna spotted earlier. 
The brunet raised an eyebrow at few who still stood up, sneering at the ex-Decimo.
"Why should we listen to you?  You're just a--!"
Swish.  Smack!
The boy who spoke up had his head thrown back, a piece of chalk crumbling as soon as it made contact with his forehead.  Everyone stared, gobsmacked, at the unconscious boy below.  The rest of the arrogant delinquents quickly sat down, sweating bullets as they gave a wary gaze at the eye-smiling brunet teacher.
Tsuna then opened his eyes, narrowing them into slits.  They glowed briefly.
"Does anyone else have any questions?"
Everyone, excluding the Vongola group, shook their heads frantically, making Tsuna eye-smile again.
"Good~and I believe everyone is here too~" Tsuna glanced at his attendance sheet, checking that everyone was there. "Let's begin class now~!"
For the past hour, the 'Dame' Sensei surprising taught Geometry well.
~~
"Wow!  I actually understand what he just taught us!"
"I know right?!"
Everyone murmured to each other as they exited classroom, walking to the cafeteria to get their lunches.
Tsuna chuckled at the words they whispered to each other.
'Of course...that spartan tutor's teaching would never go to waste.' The brunet sighed, going over what he found out about the 'him' of this world.
'It seems that Mom died a long time ago, and Dad's still working for Vongola.  That bastard doesn't even know that Mom's dead...I was still Dame from preschool through college...haha, Reborn would've killed this world's me for being so pathetic.'
Tsuna let a wry smile slip to his face as he leaned back into his chair, covering his face with one arm as he kicked his legs onto his desk.
The brunet sighed, relaxing and breathing softly in the supposed empty room.
"A-Ano..."
Sunset-orange snapped open as Tsuna lifted his arm slightly, spotting a blonde that looked so much like Giotto; blonde hair and sky-blue eyes.  Tachibana Takehito.  That was the name of the Vongola Decimo of this world.
Tsuna smiled before stretching; this one reminded the brunet of his Dame-Self back then.
"Hello, Hito-kun, what can I do for you?"
Hito stuttered slightly, rubbing the nape of his neck before his Storm Guardian stepped in--Tsuna's ex-Storm Guardian, Gokudera Hayato.  It added a small scar to the brunet's heart, but he continued to smile.
"Don't get so familiar with the Tenth!  Or I'll blow you up!"
Tsuna laughed and decided to act like Takeshi, Tsuna's ex-Rain Guardian.
"Are those fireworks, Hayato-kun?"
The bomber spluttered.
"F-Fireworks?!  THEY'RE DYNAMITES!"
Tsuna, in turn, laughed again, raising his hands up in surrender.
"Maa, maa, gomen for making you angry!"
Hito frantically tugged at Hayato's sleeve, trying to calm the bomber down as a raven suddenly laughed merrily.
"Haha, sorry for Gokudera's grumpy mood!"
Tsuna waved his hand dismissively, grinning back at the happy-go-lucky baseball player, Yamamoto Takeshi--another scar to the brunet's heart.
"Haha, it's fine, it's fine...anyways!  What do you all need?"
Then he heard it.
A voice he missed dearly.
The voice of his Father-figure.
"Ciaossu!"
'Re--'
"REBORN!  What are you doing here?!"
Tsuna gazed at the baby that stood a few feet away from him, unconsciously clenching his hands under his desk.
The fedora-wearing Spartan was still in his cursed form; Tsuna frowned mentally.
'I think I can--'
"Sawada Tsunayoshi, right?"
The said brunet blinked out of his musing before smiling brightly at the suit-wearing baby.
"Hello...so you're Reborn-kun."
Tsuna straightened his back slightly, going into his 'boss' position.  The baby hitman, Reborn, smirked slightly, eyeing the way the brunet straightened himself.
"Mm.  You seem...different."
Tsuna chuckled in return.
"Hmm...I've been hearing that a lot lately..." Tsuna's eyes glowed momentarily. "And you don't seem to be a normal baby, Reborn-kun?"
Reborn simply smirked wider, pulling his fedora down.
"Humph...you're quite the interesting one..."
The baby jumped away, landing on Hito's hair as he kept on smirking.  Tsuna smiled once more, intertwining his fingers and resting his chin on them.
"So~what did you want, Hito-kun?"
The said blonde snapped out of his revere.
'He held a normal conversation with Reborn!  The demonic spartan!  Hieeee!' "A-Ano, I just needed to know if you were fine...you looked kinda bad yesterday..."
Tsuna blinked before chuckling.
'A caring heart...perfect for Vongola's future.  But he can't have too much of a kind heart; he'll have to make some hard decisions some day.' "Maa, I'm fine!  Never been better!"  Tsuna stretched again, stifling a yawn as he did so. "...Finally met a relative of mine...you can say he's my grandpa."
Tsuna held a thoughtful expression before grinning brightly.
"Anyways!  Thanks for your concern...but shouldn't you be getting your lunch?  Lunch period is almost over..."
Hito blinked before letting a girlish shriek loose, running out the door; Hayato and Takeshi dashing after him, Reborn still on his head.
Tsuna chuckled.
"He certainly reminds me of my younger self..."