Meeting Cozzato and Creation of Vongola Edit
G was Giotto's childhood friend. He helped Giotto form the vigilante group that became the core of the Vongola Famiglia. Like Giotto, he also shares a close friendship with the Simon Primo, Simon Cozzato. Along with Giotto, he met Cozzato when they returned his wallet that he dropped on purpose for their acquaintance, Paolo, due to his master's horrible treatment towards him. They became friends after Giotto revealed that they had also done the same thing for Paolo by dropping off the same amount of money they had. When Franco, a florist and acquaintance of G, Giotto, and Cozzato was attacked and heavily injured by thugs because he refused to give them a 90% off discount, G and Giotto arrived at his shop and had enough of it, prompting Cozzato to suggest a vigilante group if the law couldn't protect them and the civilians.
The Oath Between Vongola and Simon Edit
During the middle of the massive Mafia war between Vongola and its rival Family, Giotto, G, and the other Guardians discussed their next tactic in the Vongola Mansion until Knuckle interrupted and informed them that Cozzato and his Famiglia were cornered within the enemy's territory. When Demon offered to help the Simon, knowing Demon Spade's true intention, Giotto ordered G and the rest of the Guardians to disguise themselves as Demon Spade's subordinates and secretly save Cozzato and his family. When they arrived at Cozzato's place and revealed themselves, G told Cozzato to trust them and leave the rest to them while he and Cozzato went to where Giotto was. After he safely escorted Cozzato and his Famiglia to a safe place where Giotto was waiting for them, G became the witness of the oath made by both Giotto and Cozzato.
Along with the rest of the first generation (minus Daemon), he eventually relocated to Japan with Giotto.
When Tsuna and the others return to the past with Uni to train before battle with the Millefiore, Uni summons Vongola Primo and was told that the First Guardians of the Vongola will observe them to see if they are worthy to inherit the Vongola's true power. At night, he appears from the Vongola Storm Ring in front of Gokudera at the same time as the other Primo Guardians and states that he cannot wait to see Gokudera's resolve after hearing Gokudera's declaration that he will pass with his pride as Tsuna's right-hand man on the line.
Rain Guardian Succession Trial Edit
G watches Ugetsu's second trial, and after Yamamoto passes, G stands on the roof of the shrine with Ugetsu and states that he is being too soft for giving Yamamoto a second chance. Ugetsu laughs at this, making G questioned what was so funny, to which Ugetsu answers that Tsuna and his Family greatly resembles them.
Storm Guardian Succession Trial Edit
During Gokudera's trial, he disguised himself as Gokudera while Fon gave him some time by stalling Gokudera, who believed that Uri went hiding in the bushes, prompting him to go search for Uri until the end of school. G goes to school and constantly helps Tsuna in a calm and indirect manner, the way a right-hand man should be. On their way back from school, a group of school thugs who Gokudera had beaten up yesterday appear, but they are easily beaten by G, who then encounters the real Gokudera, along with Fon and Uri. He then drops the disguise and asks Tsuna how he feels about his performance. Tsuna states that he was very reliable. Hearing this, G then tells Gokudera that his irresponsible behavior only bring more danger to Tsuna instead of protecting him, deeming he is not fit to be the Guardian of Storm, much less Tsuna's right-hand man, and thus, he told him to return the Vongola Ring and go back to Italy.
However, Tsuna protests and says that even if he is not fit to be a Guardian or perfect right-hand man, Gokudera is still his precious friend and will not let him go. Gokudera then declares that even if he doesn't receive his inheritance, he will still stay to protect Tsuna, and that his resolve is firm. Seeing how strong their bond is, which is very important to become right-hand man, G deems him worthy. With Tsuna and Gokudera confused, Fon then explains to them the meaning of the trial. G says that one cannot serve as a right-hand man if the boss doesn't completely trust him, but if their bond is firm, they could face any enemy that they encounter. Gokudera successfully completes the trial and receives the inheritance.
Afterwards, G stands by the shrine a while before Giotto appears, stating that even without his Hyper Intuition; Tsuna was still able to realize that he was a fake. G states that it's natural because they are carrying on the Vongola they created as he stated that he didn't regret a single bit during their times in the past.
Mist Guardian Succession Trial Edit
Later, at Namimori Shrine, he along with other the Guardians and Giotto meet to discuss the trials so far, and the one yet to come. All of them look worried since the next trial will be Demon Spade's and feels that the trial won't goes well as they hoped. The next day, he along with the other Guardians and Giotto watch the confrontation from afar, and debate on whether they should interfere or not. However, Giotto stops any of the Guardians from interfering even after G reminded him of Demon Spade's betrayal. A few moments later, G once again questions Giotto was he really sure of letting Demon Spade's trial to continue and assures that what happened in the past wasn't his fault because Demon had already chosen a different path from the start, but Giotto persists that Demon is still his Guardian.
After Demon Spade's trial is finished, he and Giotto, along with the rest of the other Guardians, return to the Vongola Rings.
During Tsuna's fight with Byakuran, he appears along with Giotto and the other guardians from the Vongola Rings after witnessing Tsuna's resolve, while ridiculing Gokudera's condition. He allows Giotto to do as he pleases like he always does.