Bob is the founder and guild master of the Blue Pegasus guild, a legal wizard guild on the continent of Fiore. He is an elderly man with a bald head and a heavy-set build, known for his distinctive and flamboyant fashion sense. Bob typically wears a purple spaghetti-strap shirt, a large gold and fuchsia hoop necklace, and pink and purple vertical-striped shorts, completing his look with red lipstick and blush. Despite his age and size, he possesses a pair of small, white wings on his back that allow him to fly, though only to a limited extent. In his younger years, his appearance was drastically different; he had a slender figure and short, side-swept black hair, often dressed in an aubergine-colored suit.

In terms of personality, Bob is a very friendly and sociable individual, but he behaves in a loud and effeminate manner. He has a notable fondness for young, male mages, around whom he acts especially flirtatious and forward. Despite this lighthearted and sometimes comical demeanor, Bob is a deeply understanding person who holds strong convictions, particularly regarding the treatment of spirits and the abuse of magical power. He has a serious and angry side that surfaces when he witnesses cruelty; he becomes firm and darkly solemn when confronting those who mistreat their allies, such as when he scolded his own mage, Karen Lilica, for using her Celestial Spirit as a tool and a shield.

Bob's motivations are rooted in a sense of responsibility and care for his guild members and the magical community at large. He left the Fairy Tail guild, of which he was a former member and an old friend of its master, Makarov Dreyar, to create Blue Pegasus. As a guild master, he attends provincial meetings and participates in critical events affecting the wizarding world. He plays a role in the larger narrative during the conflict with the dark guild Oración Seis, where his guild is one of several that ally to stop them. He is also present during the Grand Magic Games arc, where he oversees his guild's participation, strategizes by sending his strongest mages to compete, and joins the other guild masters in confronting threats like the impending attack of ten thousand dragons.

Key relationships define much of Bob's role in the story. His oldest and most significant connection is with Makarov Dreyar, the master of Fairy Tail, with whom he shares a long history and mutual respect. He also maintains a friendship with other guild masters of his generation, such as Goldmine of Quatro Cerberus and Yajima. Within his own guild, a crucial relationship was with the Celestial Spirit mage Karen Lilica, whom he repeatedly confronted about her abusive behavior towards her spirits, specifically Aries. After her death, which resulted from her actions, Bob was the one to deliver the news to her spirit, Leo. He also shows a caring, if somewhat overwhelming, affection for his other guild members, such as Ichiya and the Trimens.

Bob's character does not undergo dramatic transformation, but the narrative provides context for his development through glimpses of his past. His history as a handsome, capable young man who was once a member of Fairy Tail contrasts with his current, more eccentric appearance, suggesting a long and eventful life that led him to found his own guild. His principles regarding the treatment of spirits remain steadfast, demonstrating a consistent moral core that has not changed over the years.

Regarding his abilities, Bob is a skilled wizard. He is able to use a unique form of magic that allows him to phase through solid objects, as demonstrated when he passed directly through a bar counter during a conversation. In addition to this unnamed phasing magic, his small white wings grant him the power of flight, enabling him to hover and move through the air. While his overall combat prowess is not extensively displayed, his position as a guild master and his past as a member of Fairy Tail indicate a significant level of power and experience.