Ryosuke Sugiyama's Detective Series 12-book set. These were detective books that my child loved. Enjoyable for parents and children. Some books have covers, others do not. While there is some wear and tear, there are no noticeable stains or folds. As my child was reading them, there is a possibility of oversight. Please understand that these are used items. Detective in "Ready, Set, Go!" Detective in "If You're Happy" The World's Best Detective The Password is Detective Maybe a Detective Detective Day and Night The Detective Returns Detective Without Realizing It We've Been Waiting for You, Detective Detective Always Thank you for your consideration.