The character referred to as Grandfather Blas in the Dragon Quest: Dai no Daibōken series is most commonly known as Brass. He is an elderly monster, specifically a Lump Shaman, who plays a crucial role as the adoptive grandfather and guardian of the series' protagonist, Dai. Living on the remote Dermline Island, Brass found a human infant who had washed ashore and took him in, raising the boy as his own grandchild and naming him Dai. This makes Brass the foundational figure in Dai’s early life, providing a loving and safe home away from the conflicts of the wider human world.

Despite being a magician, Brass is characterized by his kind, fussy, and somewhat ineffectual nature. He is a caring and well-meaning parental figure, but his attempts to train Dai in the magical arts are a consistent failure, as the boy lacks the focus or aptitude for spellcasting. This creates a gentle, comedic dynamic between the two, with Brass often fretting over Dai’s lack of discipline and magical talent. However, his motivation is pure and simple: to protect Dai and ensure he grows up safely. He dreams of Dai becoming a great mage, though he eventually comes to accept the boy’s natural path as a warrior.

Brass’s primary role in the story is to serve as Dai’s anchor to a peaceful life and a source of emotional support. He is the one who tells the young Dai the legends of the hero Avan, sparking the boy’s initial dream of becoming a hero himself. Though he does not join Dai on his quest, Brass remains a symbol of home and normalcy. His most significant narrative contribution occurs when he is kidnapped by the Dark Army’s Zaboera. Using dark magic, Brass is brainwashed and forced to fight against Dai, a traumatic event that tests the hero’s resolve. This plot point showcases Brass’s importance as Dai’s vulnerable heart, and his eventual rescue by Popp, who uses a protective golden barrier to break the brainwashing, reinforces the theme of friendship and loyalty.

Key relationships define Brass’s existence. His bond with Dai is the most central, a genuine and deep family connection. He is also the caretaker of the other friendly monsters on Dermline Island, including Dai’s best friend, a Golden Metal Slime named Gome. His interactions with the heroes, particularly the mage Popp, highlight his role as a non-combatant who must sometimes be protected rather than a fighter who protects others. Unlike the fierce warriors and powerful mages who accompany Dai, Brass represents the innocent civilian whose safety is a core motivation for the heroes’ journey.

Over the course of the story, Brass undergoes a subtle but meaningful development. He begins as a slightly comical, nagging grandfather figure who cannot control his adoptive charge. After the traumatic kidnapping incident, he gains a deeper appreciation for Dai’s growth and the dangers of the world, though his fundamental nature remains unchanged. He ultimately returns to Dermline Island after being rescued, confident in Dai’s ability to complete his quest, and in the series' epilogue, he finds happiness as his home becomes a peaceful haven for former enemies, including the reformed warrior Crocodine.

In terms of abilities, Brass is identified as a monster magician. He possesses knowledge of magical spells and can perform enchantments, but in practice, his abilities are far outclassed by those of the human mages in the series, like Popp and Matoriv. His magic is largely used for minor tasks or protective purposes rather than for combat. His greatest strength is not his magical power but his unwavering, fatherly love and the stable, nurturing home he provided for a boy destined to save the world.