The Screwtape Letters/YMMV


 * Evil Is Cool: Averting this is pretty much the whole point, as C.S Lewis was aware of this trope. Not only is Screwtape himself a stuck-up, grumpy, backstabbing killjoy and a member of Hell's middle management, but he gives tips to Wormwood on how to minimize how much The Patient can enjoy sinning.
 * Harsher in Hindsight:
 * Screwtape refers to atheism as their hot, new weapon in the story. Since WW2 in real-life, there have been numerous attacks - with various means including violence - on various religions and religious peoples by atheistic people and groups.  Worst of all are Marxist regimes including Soviet Russia (the first nation in recorded history to have a goal of purging religion to replace it with atheism and had a government-approved League of Militant Atheists group), North Korea's Kim Dynasty and Cambodia's Khmer Rouge which tried to violently purge religiosity and the people who refuse to apostatize.  There's also been controversies such as those of the New Atheism movement and their arguments.
 * In the story, Hell has a Philological Arm trying to redefine words to lead people astray. While the book didn't invent the concept - it's cropped up before in fiction and real-life, since then there have been disputes over terms  in real life that are either sensitive (such as the definitions of "rape" and "Islamophobia") or powerful (such as the definition of "religion").
 * Moral Event Horizon: Subverted; Screwtape often argues that the task of making the patient an unrepentant sinner is usually best accomplished without any kind of spectacularly evil act on the patient's part.
 * Some Anvils Need to Be Dropped: The story is unsubtle on Lewis’ beliefs, however many agree this is to the story’s advantage. It certainly helps that many of Lewis’ comments on things like corrupt churches, religious fanatics, atheism and lust have only gotten more relatable due to subsequent events.