This is a set of 14 "Oshiri Tantei" (Butt Detective) books. Oshiri Tantei Series: ① The Purple Lady's Code Case ② The Giant That Disappeared in the Dark Night ③ The Immortal Robbery Gang ④ Detective vs. Phantom Thief ⑤ SOS from the Ruins ⑥ The Detective Agency in Danger ⑦ The Mystery of the Observation Tower ⑧ The Phantom Thief and the Targeted Bride ⑨ Who Gets the Lucky Cat?! ⑩ Oshiri Tantei's Love?! Curry Case Picture Book: Oshiri Tantei Pupupu! The Mystery of the Missing Bento Manga: ③ The Jungle Full of Traps ⑦ Chief Maltese and Chief Chihuahua Some books in the Oshiri Tantei series have covers, while others do not. Many of the covers show signs of use, but the books themselves are relatively clean.