Olivia Wolf and the Extra Moldy Sandwich

"It seems like just another ordinary day in Monstrocity, where monsters and humans live peacefully side by side. But when a teacher goes missing at school, it's up to Olivia, a brave werewolf girl, together with her friends, Bela the vampire, Fred the fly, Sam the invisible man and Elliot the human, to save the day! Where could Professor Swamp be? And could Fred the fly's missing moldy cheese sandwich have anything to do with his disappearance?"--