Rim is a dragonoid capable of shifting between two forms.

In her draconic state, she towers as a formidable creature adorned with iridescent magenta scales. Luminous green eyes with slit-like black pupils pierce through shadows, while ivory horns arch protectively around her skull like a crown.

As a humanoid, she embodies a youthful figure with pale skin, cascading pink hair, and striking emerald irises encircling crimson pupils. Magenta horns and scattered scales trace her limbs and torso, contrasting her ragged, full-body garment—a threadbare gift from Kinji Ninomiya.

Tasked with preserving the dungeon’s magical equilibrium, Rim abandons her guardianship when Kinji’s promise of sustenance overpowers her duty. Her departure fractures the dungeon’s energy, unleashing chaos and awakening the Demon Lord—a entity bearing an uncanny resemblance to her twin sister.

Once driven by voracity and indifference, Rim gradually embraces empathy and duty. Her transformation peaks as she confronts the consequences of her choices, channeling newfound resolve to shield Sky, the younger sister exposed as the Demon Lord. This arc traces her metamorphosis from reckless instinct to selfless guardianship, underscoring her resilience and evolving bonds.