Pretty Boy Detective Club (manga), volume 2 — Nisioisin

Mayumi Dojima has just become the newest member of the Pretty Boy Detective Club when her first challenge as Mayumi the Seer literally falls into her lap: a suspicious businessman drops a wad of counterfeit bills on the sidewalk, and suddenly the games are afoot! At a shady casino operating out of their rival high school's gymnasium, the Pretty Boys encounter a fiendish new foil -- leading to a nail-biting showdown between beauty and fraud… And just when things seem to have quieted down, a chance discovery in the art room leads the Pretty Boys to 33 mysterious paintings, and a bizarre kidnapping that took place at Yubiwa Academy seven years earlier -- ?!