Beerain, a bee-type Invectid, emerges as the sole female member of the Big Four—elite generals serving under Mantid. Renowned for cunning over brute force, she wields a whip in battle and commands swarms of Buzzrays, insectoid soldiers engineered for warfare. Her early tactics dismiss honor, openly declaring her disregard for fair play. Yet through encounters with allies and adversaries, she gradually acknowledges honor’s strategic merit.

Her loyalty to Mantid fractures as his brutality and ambition escalate, particularly upon uncovering his plot to monopolize the Oracle Keys’ power. While reassessing her allegiance, her devotion to fellow general Buguese persists, underscored by simmering romantic tension. After Mantid’s betrayal, she allies with Buguese and Stags to oppose him, prioritizing the Invectid homeland’s restoration over blind loyalty.

A pivotal shift occurs when injuries leave her vulnerable, rescued by Grasshop and Princess Sparkle. Their care challenges her lifelong animosity toward humans, fostering reluctant acceptance of potential coexistence. Despite lingering distrust, she aids Spider Riders by disclosing secrets to navigate the Invectid Nation’s labyrinth.

Physically distinctive, Beerain sports pink skin, a crimson face mask, and cropped orange hair, paired with expansive wings enabling flight. These wings regenerate after damage. Her attire—a white skirt and billowing limb accessories—sets her apart among Invectids.

Schemes define her trajectory: infiltrating villages using hallucinogenic Blossoms of Darkness under the alias “Rain,” or impersonating Prince Lumen’s childhood friend Lady Noia to steal an Oracle Key. Though Spider Riders repeatedly thwart her plans, her arc culminates in joining the final assault against Mantid. Witnessing sunlight’s return to Invectid lands, she achieves the goal that fueled her relentless crusade.