A shape-shifter water spirit with a nasty habit of sneaking into children’s dreams and drowning them in their sleep. They apparently feed from the fear and death-throes of prepubescent victims. They’re generally considered part of the The Dream include any people who live between dimensions and subsist on the essence of dreams of others. More because they’re most dangerous within dreams; while they’ve been known to attack physically, dragging people into the water to eat, they’re rarely seen in waking life.
No one really knows what they look like because they rely on imagery already in the dreamer’s mind.