The Filthy River of Lethe

AKA-
 * River of Forgetfulness
 * Gulf of Depression
 * Entryway to Letum
 * Entrance to Carcerem

The River of Lethe is the open Entryway of Letum. Spirits (Goners) or Sentients (Wanderers) that go here become lost with hopelessness, depression, and confusion due to the River's Filth of Forgetfulness. The Djinn Mother of Labo was named after this place for losing her purpose as a Sentient, and this is why Labo is struck with depression.