Dione Nephilim is a gigas, a rare giant race, residing near a harpy village. Her immense size defines her physically, requiring scaffolding for interactions with smaller beings like humans even while seated. She possesses long green hair, and her eyes remain hidden from view. She moves with deliberate care to avoid harming smaller creatures or causing environmental damage, though each step risks sending tremors through the earth or triggering landslides.

Her personality exhibits profound gentleness and consideration, especially towards smaller life forms. She actively avoids stepping on animals and expresses constant concern for their safety, demonstrating a sweet disposition in interactions.

Her relationships include a long-standing friendship with Skadi Dragenfelt, dating back to Lindworm's founding era as a city for humans and mythical creatures. Another friend is Illy, a harpy who visits her mountaintop dwelling. Though centuries old, she is considered young for her species.

Her abilities stem from her gigas physiology, granting extraordinary physical strength that allows her to lift humans effortlessly. A single sneeze demonstrates her uncontrolled power, capable of blowing a person a significant distance. Her lifespan vastly exceeds other known species, including dragons, permitting sleep for durations like 10,000 years without adverse effects.

Her medical history includes contracting a common cold approximately ten years prior, coinciding with Lindworm's earlier period. Her species' low metabolism significantly prolonged her recovery, necessitating extended rest. This illness persisted until treated by Glenn Litbeit during his visit to the harpy village.

Her surname "Nephilim" references mythical giant hybrids from Hebrew tradition, born from unions between human women and fallen angels known as Grigori.