The largest library in Dandong is near Liudaogou Square, on the left of the old TV factory. The new building is in the new city, but I don't know what it looks like.

You want to buy light novels, I don't understand. I am over 90 years old, and I don't know what a light novel is. However, the library only borrows books and reads books in the library. If you don't sell books, you have to go to the bookstore to buy books. There is the largest bookstore in Dandong diagonally opposite the Cultural Palace in Qi Jing Street. It is estimated that the bookstore has nothing to do with novels (it seems to be going out of business), or I suggest you go to JD.COM Mall or Amazon.com and have a look online. Fast and discounted ... genuine.