Giaccio is a game-exclusive Bertesco Famiglia mafioso from the third installment of the Fate of Heat DS game Katekyō Hitman Reborn! DS Fate of Heat III - Yuki no Shugosha Raishuu!
Ryohei and Kyoko went to the only factory at Catafalco Island after gaining the key to the Sun Temple. When they reached the entrance of the temple, however, they were stopped by Giaccio and his henchmen. After defeating Giaccio's subordinates, Ryohei challenged him to one-on-one battle, which Giaccio accepted, though he was ultimately defeated.