Goro Mutsumi’s life is marred by relentless misfortune—chronic unemployment, financial instability, and social isolation, particularly in romance. His lifelong streak of tragedy began in childhood with recurring pet deaths tied to his circumstances: a goldfish perishing during a power outage, a parakeet succumbing to a poorly healed wing injury, and a rabbit dying of loneliness in his absence. These losses bred lasting guilt and a fear of bonding with animals.

A prophecy from a fortune teller disrupts his despair, heralding guardian angels who manifest as human incarnations of his deceased pets. Unaware of their origins at first, Goro discovers their purpose: to reverse his misfortune by resolving their own unresolved traumas from past lives. Their mission expands as they confront the Saint Beasts, vengeful entities targeting Goro for his past identity as Seijya, a sage who stole their divine powers to prevent humanity’s extinction and establish equality between humans and animals.

Later, Goro pursues veterinary work despite ongoing hardships, channeling his empathy into animal care. His relationship with the guardian angels deepens into a familial bond defined by mutual defense and loyalty. Though initially vying for his attention, the angels gradually unite, prioritizing his safety over personal rivalry, influenced by his nurturing nature. Even factions among the Saint Beasts begin reconciling with him upon recognizing Seijya’s selfless motives.

Goro’s essence remains unwavering—gentle, compassionate, and fiercely protective, even under existential threat. His history as a bridge between species fuels his dedication to harmony, a legacy spanning his past and present. The narrative intertwines his growth in accepting support with the angels’ evolution, all while confronting the repercussions of Seijya’s ancient rebellion.