I study pop culture characters in comics, cartoons, shows, books, etc., because of what I can learn about them, in terms of character development, attributes, correspondences, and how you can apply all of that to your own magical work. There's a lot of detail that's put into a character, in terms of origin, history, personality and all of these details are useful not only for developing a pop culture magic working, but really for developing an eye toward the kind of detail that can be necessary to pull off a good magical working. With a pop culture character, the details that go into the development of the character are ones that help make that character memorable to the people watching the show or reading the book or comic the character is in. If you want to create a compelling character you need to develop all of those details, because they will all help draw the interest of the audience.
How does that apply to magic? If you're creating a magical entity you want to be as detailed as possible in the creation of it. What are its characteristics and mannerisms? What is its origins, its special abilities etc.? Those details can bring that entity to life for you, and empower the magical work you do.
But lets look beyond entities to other forms of magical work. I find that paying attention to the details is essential to being successful with magical work. When I put a magical working together, I try to think of the details as part of the narrative of a story I'm writing. By taking lessons from pop culture, I've been able to put those details into focus in my magical work, so that I don't leave any loopholes in what I'm trying to accomplish.