Insanity of the Black Sheep

All Katherine McAndrews wanted was a tutor for her upcoming exam. Sounds fairly easy to obtain right? Instead the tutora gothic, stoic girl named Muchiko Kisaragihas involved Katherine in a devious plan to try and find her sister, Harumi Kisaragi, after a gruesome murder in an anime convention. After finding out that Harumis next target is a popular teen idol in Russia, Katherine and Muchiko convi...