In my story, Gold ‘n Silver, a human-hybrid wants to force me to forget my past and who I truly am. Because I am a goddess and a vampire, there is nothing mortal that can erase my memories (though they did try). So he forces me to the underworld to drink from the River Lethe.
In addition to the River Lethe of the underworld, there are also two other rivers named Leith. One is the main river that runs through Edinburgh and the other is the Water of Leith in Otago, New Zealand.