The devil wants admirers. If we think of evil as a force, a power, a personality -- some would say the devil -- what evil wants is to be admired. It wants praise for being freeing and liberating. (Never mind that it 'frees' people from health and sanity, from a joyful life.) When evil attacks good, it thinks of itself as powerful and brave -- and demands to be called such. Evil is looking for followers. It wants respectability. It wants recognition for being right -- even if it denies that the idea of "right" has any legitimacy. (The anti-religious movements tend to sound just like a bad religion, sooner or later.)
Evil is content to begin with us: To make it so that people become greedy for admirers, and praise, and respect. In our personal lives, whenever we face a temptation to set our sights on these things, it's a temptation to become less godly.
Evil will teach us to look at self-control as a bad thing. It teaches us to mislabel decency as "inhibition". It uses "irreverent" and "wicked" as praise words, and excuses rudeness -- or outright spiteful verbal attacks -- as humor. In the field of sexuality, anyone who holds the ideal of monogamy is insulted as "prude" or mocked as "Puritanical". Those who promote lifestyles that require artificial hormones or medically unnecessary surgery are applauded as "groundbreaking". The tools used are honor and shame. And once people have done things that are inconsistent with decency, it's awfully easy to join in the attacks on decency, to become followers of whoever will boldly claim that there is nothing wrong.