Yoenki, or Yoenhime, is the vengeful sister of the demon Suikakujū, a pivotal antagonist slain in the series’ conflict. Consumed by grief over her brother’s death, she directs her wrath toward Amano Jyaku, whom she blames for his demise. Her pursuit of retribution is cunningly exploited by the scheming Münchhausen II, who reforges her into a formidable entity through dark transformation, weaponizing her fury to advance his plot of seizing control over the Chōjin and subjugating the three realms.

Driven by intertwining threads of personal loss and sinister influence, Yoenki’s augmented powers under Münchhausen II’s machinations escalate her into a lethal force. She emerges as a pivotal adversary during the survivors’ odyssey to Osaka, her wrath reaching its zenith in a decisive clash against Amano Jyaku and his allies. Though her rampage is tethered to avenging Suikakujū, it inadvertently fuels the larger chaos orchestrated by her manipulator.

Entrenched in the demonic hierarchy, Yoenki’s lineage ties her to her brother’s legacy—Suikakujū once rivaled Amano Jyaku in their infernal order. While her origins remain shrouded, her narrative embodies the destructive spiral of vengeance and the peril of external control, mirroring the apocalyptic world’s themes of fractured loyalties and exploited sorrow.