Pietro was a close friend of Leorio.
He passed away due to a treatable illness, but Leorio couldn't save him because the necessary surgery was beyond his financial means. This loss filled Leorio with deep regret, motivating him to become a doctor so that he could prevent such tragedies in the future. Driven by this goal, Leorio participates in the 287th Hunter Exam.
(Source: Hunterpedia)










