You might be frustrated by the library never having a complete manga collection on its shelves at any given time, but the 12 year old checking out 14 volumes of One Piece at once is vital to the library ecosystem. He's like the sea otter keeping the kelp forest from being devastated by an excess of sea urchins.
To those curious some other keystone library species include:
—the retirees who’ve read more murder mysteries than I’ve had hot meals
—the paperback romance girlies (gender neutral) who check out every single bodice ripper the second it hits the shelves
—the dads very slowly making their way through a ‘1001 movies to see before you die’ list
—the one-man criterion collection who checks out like, three movies per day and brings them back the next. (TV series are only a minor roadblock.)
—kids who like Minecraft
---The new parents checking out 47 picture books for their 7 month old baby who clearly has nothing going on in their head except the Wii Sports Resort theme song