⦗🧛⦘ ⦓☾✹✯𝚅𝚒𝚎𝚕𝚕𝚎✯✹☽⦔ (viellain)

In the early days of paperback books, the paper used was very low quality, usually newsprint. Consumers rejected the soiled and discolored appearance of the pages. Publishers hit upon the notion of "staining," which made the paper look fresh, even pretty, and most important, prolonged the shelf life of their books.