Born in Isger's Chitterwood, Fumbus's early life was practically idyllic, at least by goblin standards. The Chitterwood has been largely left to the goblins since the end of the Goblinblood Wars nearly twenty years ago, its goblin inhabitants now free of the militant influence of their hobgoblin cousins, most of whom were eradicated or driven out of Isger at the closing of the war.

Fumbus had the honor of serving as apprentice to the Fire-Eater goblin clan's chief pickle-maker, a position which gave him a fair amount of standing amongst his kin. Unfortunately, Fumbus had a particular penchant for experimentation that led to spectacular failures as often as it led to new delicacies. When a particularly unstable batch of "spicy pickle brine" exploded in the middle of the Fire-Eater encampment, Fumbus fled the Chitterwood, fearing that the reprisal from his fellow goblins for destroying both the clan's precious pickle barrel and a significant supply of cucumbers would be swift and violent.

Fumbus's initial forays into the wider world were truly terrifying. Scavenging from human farms usually ended poorly, as vicious dogs and horrifying horses would bite, chase, or stomp the poor goblin if they caught wind of his presence. The humans themselves were often even more terrifying, and Fumbus found himself fleeing pitchfork-wielding mobs with stolen, smelly shoes (easiest to find without a light and useful as either food or clothing) tucked under one arm far more often than he found a safe place to fill his belly and sleep. Fumbus's life likely would have ended at the hands of one of these mobs had he not encountered a passing half-orc Pathfinder named Droven whose initial reaction to the little goblin was humor, rather than fear or violence. Used to dealing with a certain amount of prejudice and distrust himself, Droven dissuaded the mob from pursuing their vendetta against the goblin and allowed Fumbus to accompany him on his mission.

Droven's heroics entranced young Fumbus, particularly the alchemical fire and other concoctions the half-orc used to defeat his opponents. When Droven completed his mission for the Pathfinder Society, he brought Fumbus back with him to Absalom. Droven helped secure a home for the little goblin in the Puddles district, where Fumbus's presence would be less likely to cause a stir, and shared what he knew of alchemy with the eager goblin. While Fumbus was terrified at the thought of needing to write down formulas, his mind was sharp and he quickly mastered the art of reading; to Fumbus, collecting these foolishly discarded thoughts was no different than surviving off the trash and scraps left on the outskirts of towns and cities. Fumbus came up with his own system for creating and remembering formulas using small tokens engraved with pictographic runes and a series of leather cords, which he would use to bind certain ingredients in specific orders. Together these implements allowed him to practice alchemy without risking his goblin soul or precious thoughts by performing the obscene act of writing anything down. Of further benefit to Fumbus, his new home's location in the Puddles allows the little goblin to experiment with all manner of inflammable and unstable concoctions with little fear of wreaking destruction beyond the building's water-logged rooms.

Droven offered to sponsor Fumbus into the Pathfinder Society, but the goblin was so impressed by Droven that he truly believed he would not be able to pass the Society's rigorous entry exams. Determined to prove himself, Fumbus busily applied his time and energy to creating new alchemical formulas and perfecting his system for recording his discoveries. As Fumbus's confidence grew, he began to believe that perhaps he might find a place in the Pathfinder Society after all. Skulking through the alleys of Absalom, Fumbus made his way to the Grand Lodge. Upon his arrival, Fumbus learned that Droven had left on a mission several weeks ago and was overdue to report in; his ship was believed lost at sea. Droven had left a letter of sponsorship as well as some funds to secure the goblin a chance to learn at the Society's institutions but Fumbus was unwilling to begin his training without the half-orc present.

Months have passed and Droven has still not returned. Fumbus spends his time perfecting his alchemy, seeking news of his lost friend, and looking for opportunities to ingratiate himself to the Pathfinder Society, despite multiple assurances from the Society's members and leadership that Fumbus's welcome was already secured by his half-orc friend. Something in Fumbus's mind refuses to let go of the idea that he must prove himself to be a worthy explorer of the same caliber as Droven, whose heroics and skill are unmatched in Fumbus's view. The little goblin has made a decision that he holds sacrosanct: he will earn his entrance to the Society by either finding his friend Droven and bringing the half-orc home, or by performing a truly heroic act worthy of the reputation Droven holds in Fumbus's own eyes.