Set in the Kokuyo arc

The instant Tsuna set his eyes on Mukuro he smiled.

The instant Mukuro saw that look he thought. 'Oh No should've known that was him.'

"MUU-KUN~!" Tsuna magically appeared next to him and clung to him like a bur. "I've MISSED YOU!" Tsuna started shaking him around like a rag doll.

As Mukuro was swung helplessly around everyone else was wondering what is going on?

"Dame-Tsuna how do you know Mukuro?" Reborn asked irritated at the fact he had no idea what was going on.

"Muu-kun~ was my first best friend when I was six. I met him here before it was abandoned, and at first he tried scaring me but I clung to him anyway. But we got separated when he protected me from the Estrano." Tsuna replied with a smile as he stopped shaking Mukuro, who fell limp in his arms, and clutched him possessively.

"Kufufufu who would've thought you'd become Decimo, Tsunayoshi." Mukuro chuckled slightly dased. "Especially since they don't know your true power, Kufufufu."

"Aww you weren't supposed to tell them!" Tsuna said pouting slightly.

Suddenly the Vendice came and Tsuna could feel Mukuro shudder, instantly marking them as an enemy.

"Muu-kun do you mind..." Tsuna whispered in his ear and a mist barrier instantly covered them from view of Reborn and the others.

*Time skip brought to you by Sadistic Cat/Kiaeol hehehehe*

The mist barrier vanished revealing a happy Tsuna still clutching Mukuro, no Vendice and a suspicious burn mark on the floor.

"Dame-Tsuna what happened?" Reborn demanded but was ignored as Tsuna started walking home carrying Mukuro bridal style.

Reborn tried to kick his student who dodged without disturbing Mukuro who fell asleep.

Reborn silently promised quadruple tort-tutoring to his student as he called the Vongola doctors to treat the injured and confused guardians.

*With Tsuna*

Tsuna somehow teleported to his room after Reborn turned away and set Mukuro down on his bed.

"I missed you so much Muu-kun, I forgot to say I love you before you left." Tsuna said laying next to Mukuro and kissing him on the forehead before going to sleep.