ANSWER:

You shouldn’t read such books that contain shirk, kufr and sorcery though it won’t impact your iman as you say. 

Allah made this clear in 4:140 👇

“He has already revealed to you in the Book that when you hear Allah’s revelations being denied or ridiculed, then do not sit in that company unless they engage in a different topic, or else you will be like them.¹ Surely Allah will gather the hypocrites and disbelievers all together in Hell.” (Quran 4:140)

QUESTION: I was curious if reading books with magical and mythological elements, such as Harry Potter, Percy Jackson, Lord of the Rings, etc., was permitted. My IMAN is unaffected by this, and I read them for enjoyment.