Mythril Lid Pod sprang from a single drop of water in the giant lake of Loess, northern Highland, a water fairy by origin. His aquatic nature allows him to generate and manipulate small amounts of water. He manifests as a small, blue-eyed fairy with silver or lilac hair accented by light blue streaks. His attire consists of gray pants, a white shirt, a light green or blue coat, leather boots, and gloves. The wing torn from him during enslavement is worn perpetually around his neck as a scarf, a stark reminder of his past.

First encountered enduring a public beating from a fairy hunter for trying to reclaim his stolen wing, he is rescued by Anne Halford. Deep distrust of humans prevents him from offering gratitude. He later seeks out Anne to repay his perceived life debt, joining her travels. Stubborn, grumpy, and sensitive, he exhibits fierce loyalty to those few he trusts. He demands use of his full name and displays energetic, talkative tendencies that sometimes cause friction with companions.

Journeying to Lewiston, he faces false accusations of stealing Anne's silver sugar, framed by another fairy, Cathy. Cleared of blame, he retaliates by consuming Jonas Anders' stolen silver sugar, humiliating Jonas publicly. He becomes aware of Anne's growing romantic feelings for Challe Fen Challe and actively champions their relationship, serving as a vocal advocate.

Beyond comic moments, he offers crucial emotional support during Anne's confinement at the Paige Workshop. He aids her in critically recreating the crest of House Chamber—an officially forbidden act necessary to help a child. His experiences mirror themes of fairy enslavement: wing-severing for control and human name imposition erasing identities. Initial animosity toward humans gradually softens through interactions with Anne, revealing his capacity for trust and growth within their solidarity.