Millibelle

Millibelle is a minor antagonist of Hollow Knight. She is a kind and trustworthy banker who protects her visitors' Geo, the currency of Hallownest, inside her small bank stand located in Fog Canyon. However, it is all a scam, as Millibelle is actually a cunning thief who tricks others into giving her their Geo using her "bank".

Biography
Millibelle is found in the left room at the base of the Fog Canyon. She explains to the Knight that she was about to close shop due to a lack of visitors, but is happy that someone came back and decides to keep her bank running. For a 100 Geo fee to open their account, Millibelle provides a service to keep the Knight's Geo safe. Even after death, the Geo that Millibelle holds will remain, and can be deposited or withdrawn at any time.

Millibelle can hold up to a maximum of 4,500 Geo, but when 2,500 Geo or more is deposited, she will vanish from her stand after the Knight leaves and rests on a bench or uses a Stag Fast Travel.

Where Millibelle ran off to is the Pleasure House located in the City of Tears, which requires a Simple Key to unlock. In the room above the ghost of Songstress Marissa is the City of Tears hot spring, where Millibelle is residing. At first she attempts to tell the Knight that she spent all of their Geo, but hitting her with the Nail causes her to drop the Knight's deposited Geo by the hundreds, plus an additional 2,500.

Trivia

 * The 100 Geo used to open the bank account is not returned.
 * Most of the additional attacking charms when equipped (Weaversong, Glowing Womb, Grimmchild, and Dreamshield) will attempt to attack Millibelle from behind the "bank", despite her not being an enemy. Any presence of these charms will make her cower from underneath her stand and refuse to be interacted with.
 * Hitting the empty stand following Millibelle's escape reveals it to be a 2D cutout, which promptly falls to the floor. Her bank sign also falls to the ground on the way out.