Mythril Lid Pod is a water fairy with silver hair featuring light blue accents, striking blue eyes, and a small stature. His attire consists of a light blue coat over a white shirt, gray pants, leather boots, and gloves; he distinctively drapes his own torn wing like a scarf around his neck.

Emerging from a water droplet in the vast Loess lake of northern Highland, he possesses the innate ability to generate and manipulate small quantities of water. His past involves capture and enslavement by a fairy hunter, who publicly tortured him for trying to retrieve his stolen wing. Ann Halford rescued him, interrupting a beating to secure his escape. Despite a profound distrust of humans, he chose to follow Ann to settle his perceived debt, refusing initially to express gratitude.

His personality is stubborn, grumpy, and sensitive, yet underpinned by deep loyalty and reliability toward his companions. He insists others use his full name and exhibits a notably talkative, energetic nature, sometimes causing friction with figures like Shall Fen Shall. He actively supports Ann's romantic feelings for Shall and encourages their relationship.

Key developments include being falsely accused by Cathy, Jonas Anders' fairy, of stealing Ann's silver sugar during their journey to Lewiston—a deception later exposed. In retaliation, he consumed Jonas's stolen silver sugar, shaming Jonas before Highland's ruler. Later, his watery origin led to a foreshortened lifespan. Saved by the diamond-born fairy Eril Fen Eril, this rescue permanently stripped him of his water-manipulation abilities.

His role transforms from a resentful individual acting out of obligation into a devoted member of Ann's group, sharing their travels and confronting challenges linked to fairy subjugation and personal sacrifice.