Reborn

Reborn  is the eponymous character of the series, the infant home tutor of Tsuna, Dino's former tutor and the world's strongest hitman. Before he received the Arcobaleno Curse, he greeted people with the word "Chaos". However, he says "Ciaossu" while he is in his cursed form due to his undeveloped vocal cords as a five-years-old. "Ciaossu", incidentally, is a combination of the Italian and Japanese greetings "Ciao" and "Ossu".Among all the Arcobaleno, he is said to be the strongest. It was revealed in a flashback that Reborn initially showed anger towards the Arcobaleno curse; however, after a period of exile, he came to accept it, asking Shamal to "erase" his old self.