A pure evil MC might stick to strict daily routines.


My MC does many of the things he does because he thinks he is the hero of the story and will always follow popular troupes and cliches even if it puts the plan or the people around him in jeopardy.


They don't have to be likable, but they have to be relatable in some way, otherwise no one will be interested. Very few of your readers will be Pure Evil (if that's even a real thing...personally I don't think so) so you'll need to find ways to make them relatable to non-evil people. Eg. If your evil character finds dealing with the mundane details of life frustrating, that's totally relatable.


Another good approach is to enunciate and further expound upon how that character sees the world. A fresh perspective you might say. A cynical pov where he thinks that everyone is selfish and even acts of help are seen as self-serving. A narcissistic pov where he believes that everything revolves around him. A manipulative, scheming character in which everything he thinks about is connected to his own interests and benefits. The thing with "evil" protagonists is, the author most of the time just makes it too personal and vents all their negativity in the characters motivations. Making the character into some kind of soyboy petty incel. Design your character, their narrations must be kept consistent with their character design. You don't have to agree about their views. You can be the most patriotic person in the world but if your character design for this protagonist is a hater of the government, then he will think like a terrorist and you will write him in the perspective of a terrorist.


Its going to come down to your writing, imho. American Psycho and Blood Meridian come to mind, maybe a smidgen of Lolita. All of those people were detestable, but the reason to read on was the writing quality.