Lethe

Lethe was one of the five rivers that flowed through the Underworld in Greek mythology. It passed through the cave of Hypnos (sleep); there, whoever drank from its waters, they forgot everything. The other four rivers were Styx, Acheron, Cocytus, and Phlegethon.

Lethe was also the personification of forgetfulness, a goddess who was the daughter of Eris, and sister to a number of siblings, including Ponos, Limos, Algea, Hysminai, Makhai, Phonoi, Androktasiai, Neikea, Pseudologoi, Amphilogiai, Dysnomia, Ate, and Horcus.