Kappa

The Kappa, often called Riverfolk, are a mysterious and mischievous race of humans who dwell within the flowing rivers of Lucis. Perfectly adapted to life both above and beneath fresh water, their bodies are sleek and smooth, built for agile swimming and effortless movement through the currents. Their gills, however, are a delicate gift—finely tuned to the purity of rivers and streams but fatally vulnerable to salt water. Even brief exposure to the sea can cause violent allergic reactions, and prolonged contact is lethal. This weakness has confined them to freshwater realms, where they have built secretive societies beneath the surface, hidden among reeds, roots, and stone.

Yet what truly defines the Kappa is not their physiology, but their voice. Their vocal cords are uniquely adaptable, allowing them to mimic with uncanny accuracy the sounds of both man and beast. They use this ability playfully—or cruelly—depending on their mood. Many tales tell of travelers hearing the familiar voice of a loved one calling from a riverbank, only to vanish when they answer. Whether out of curiosity, mischief, or greed, Kappa often lure wanderers close to steal from them or simply to revel in their confusion. Because of this, their kind has become woven into riverside folklore: warnings whispered to children and travelers alike—“If you hear a familiar voice by the water, do not answer, for it may not be who you think.” For all their tricks, however, the Kappa remain elusive, more legend than truth, their laughter echoing faintly in the rippling flow of the rivers they call home.