Ryuuji Takasu has been unlucky since birth: from his mafia father he inherited a terrifying stare, so despite his gentle nature he is considered the most dangerous delinquent in the whole area. A new school year begins, and Ryuuji is filled with hope — both his only friend Kitamura and the girl of his dreams, Minori Kushieda, have ended up in the same class as him. But there is a fly in the ointment: in that same class studies the tiny but extremely dangerous Taiga Aisaka, nicknamed the Palmtop Tiger for her fierce temper. To his misfortune, Ryuuji accidentally learns her secret…