Screwtape is the fictional tempter writing letters to his nephew in C.S. Lewis’s The Screwtape Letters. The book presents its satire through correspondence between demons.
Screwtape is an experienced senior demon who advises Wormwood, a junior tempter assigned to influence a human patient. The letters reverse ordinary religious guidance: spiritual dangers are discussed from the perspective of demons trying to encourage pride, distraction, resentment, and other failures.
A frequent mistake is to answer Wormwood, because Wormwood is the nephew and the recipient of the letters. Screwtape is the writer and instructor. Lewis published the book in 1942, and its epistolary format allowed him to criticize human weaknesses by making readers view familiar habits through an intentionally distorted demonic perspective.