Pioro Saionji is a supporting character in By the Grace of the Gods, appearing mainly in the novels and manga of the series rather than the first season of the anime. He is a fox beastkin and a lifelong merchant who serves as the head and representative of the Saionji Trading Company, a family firm that specializes in the handling and distribution of food. Pioro's business is rooted in a long family tradition: one of his ancestors was transported to this world from another one and, while trying to recreate the cuisine of his former home, built a large food transport and trading enterprise. That legacy explains both the company's focus and Pioro's own identity as a food merchant.

In terms of appearance, Pioro has a thin build and a perpetually cheerful, squinting expression, with his eyes rarely seen fully open. He speaks with a dialect resembling the Kansai accent of Japan, which gives his speech a warm, informal, and approachable quality. His personality is that of an enthusiastic businessman, comparable in energy and passion for commerce to his fellow merchant Serge Morgan. He enjoys discussing trade, exchanging opinions on business ideas, and helping others refine their commercial ventures.

Pioro's main motivations are tied to his family and his profession. He is dedicated to the success and growth of the Saionji Trading Company, and he is equally committed to passing on his knowledge to the next generation, particularly his daughter Miyabi. He supports her ambition to become a merchant, training her in the trade so that she can carry on the family business.

Within the story, Pioro functions as a mentor figure in the commercial world that the protagonist enters. Together with the merchant Glissela, he offers his own opinions on the concepts Ryoma proposes for his shop, helping him shape his ideas into workable business plans. Because his appearances take place mainly in the novels and manga, and he does not appear in the first season of the anime, his role in the broader narrative comes through his influence on commerce and on the people around him.

Pioro's family relationships are a significant part of his character. He is married to Clana Saionji, and together they have a daughter, Miyabi. Like her father, Miyabi is a fox beastkin and trains to become a merchant. She befriends Ryoma during his stay in the city of Lenaf, and she later moves to the capital to study at the Imperial Academy, where she becomes one of Eliaria Jamil's close friends. Through his daughter, Pioro remains connected to the younger generation of characters even when he is not directly present in a scene.

Pioro's development in the series is gradual and closely linked to his family and his business. He is shown as a stable, experienced presence who trusts in the abilities of those he has trained, and his daughter's progress as a merchant reflects the values he has instilled in her. His continued involvement in trade and his willingness to share his expertise reinforce his role as a dependable figure in the commercial side of the story.

Pioro's notable abilities lie entirely in commerce rather than combat or magic. He has deep knowledge of food products and the food trade, strong negotiating instincts, and experience in managing a trading organization and its distribution networks. As a fox beastkin, he also carries the physical traits of his people, most visibly fox ears and a tail, but his defining strengths are his business acumen, his enthusiasm, and his ability to recognize and support promising ventures.