Yosino Mago Zenpen [2021] [Mobile SIMPLE]

Given the phrasing, the most plausible identification is that this is related to (吉野) and a text beginning with "Mago" (孫 or 真後). In classical Japanese literature, one famous work that fits a similar structure is: Possible Identification: Yoshino no Mago (吉野の孫) – A Noh Play While "Zenpen" (前編) means "first part" or "preface," the core title Yosino Mago (using old kana spelling) strongly suggests the Noh theater piece Yoshino Mago (吉野の孫 / "The Old Man of Yoshino" or "The Grandson of Yoshino").