It’s subtle, but see if you can find the commonality on the top 20 graphic novels sold in this country in April.
Per the ICv2 website: “NPD BookScan collects weekly point-of-sale data on print books from over 16,000 locations including e-tailers, chains, mass merchandisers, independent bookstores, and more. NPD BookScan covers approximately 85% of the U.S. trade print book market. The ranks on this chart are based on piece sales. Some publishers classify titles that are primarily text, or art books, as graphic novels; we’ve removed those titles from the ranking above.”
I should note that while many of the above have wildly successful animes to promote sales, several (Chainsaw Man, Spy X Family) have not had yet, and Tokyo Ghoul’s anime ran in 2014.