Firo Prochainezo

Firo Prochainezo (フィーロ・プロシェンツォ Fīro Puroshentso) is one of the youngest members of Manhattan's Martillo Family and a skilled fighter.

He was orphaned when he was ten and picked up by the head of the Martillo family after Firo attempts to rob him. Because of this, he considers the Martillo to be his family. He is tasked with monitoring casinos to prevent cheating, and later manages those casinos after becoming an executive member of the family. Firo is a very well mannered boy and always speaks politely with everyone. In 1930, he mistakes the immortality elixir for alcohol and takes it. He later distributes the elixir at a party, becoming immortal himself. That year, he falls in love with Ennis and devours Szilard Quates, saving her and the new immortals. Despite the fact that she does reciprocate his feelings, they live together afterward and eventually marry in 2002. In 1934, he was later arrested by Victor Talbot for the destruction of public property during the bombing of the skyscraper Mist Wall and is imprisoned on Alcatraz Island. When Maiza Avaro leaves the Martillo in the 1970s, Firo is given the position as the family's bookkeeper until Maiza returns.During this time, Firo wears glasses in an attempt to look smarter. Because he is friends with Luck Gandor and Clair Stanfield, the Martillo and Gandor families are on friendly terms.

Creation
They resemble the real-life thief duo Bonnie and Clyde, being possibly based on them.

Abilities
They have an above average luck, getting out of several dangerous situations without any serious injuries (tthey took 71 years to notice they were immortal), they're also very charismatic and both "sprinkle happyness without noticing".

Biography
Firo is one of the youngest members of Manhattan's Martillo Camorra family and is a skilled fighter. He was orphaned when he was ten and picked up by the head of the Martillo family after Firo attempts to rob him. Because of this, he considers the Martillo to be his family. He is tasked with monitoring casinos to prevent cheating, and later manages those casinos after becoming an executive member of the family.[19] In 1930, he mistakes the immortality elixir for alcohol and takes it. He later distributes the elixir at a party, becoming immortal himself. That year, he falls in love with Ennis and devours Szilard Quates, saving her and the new immortals. Despite the fact that she initially does not reciprocate his feelings, due to her underdeveloped emotional capabilities, they live together afterward and eventually marry in 2002. In 1934, he is arrested by Victor Talbot for the destruction of public property during the bombing of the skyscraper Mist Wall and is imprisoned on Alcatraz Island.[20] When Maiza Avaro leaves the Martillo in the 1970s, Firo is given the position as the family's bookkeeper until Maiza returns.[21][22] During this time, Firo wears glasses in an attempt to look smarter.[22] Because he is friends with Luck Gandor and Claire Stanfield, the Martillo and Gandor families are on friendly terms. Firo is voiced by Hiroyuki Yoshino in Japanese and Todd Haberkorn in English.