The eldest reborn
Reborn is the world's greatest hitman and the Arcobaleno of the Sun. Feared throughout the criminal underworld, Reborn was afflicted with a curse that trapped him and the other six Arcobaleno in infantile forms. Despite this, Reborn continued his work until he was ordered by the ninth Vongola Boss, Timoteo, to groom the meek and hapless Tsunayoshi Sawada into a suitable successor. Thus Reborn.