"Sayonara, Zetsubou-Sensei" is a Japanese manga series created by Kōji Kumeta. It follows the story of Nozomu Itoshiki, a pessimistic high school teacher who often contemplates suicide due to his bleak outlook on life. The series humorously explores themes of despair, societal issues, and the quirks of modern life through Itoshiki's interactions with his eccentric students. The manga was serialized from 2005 to 2007 and later adapted into an anime television series. The show features a unique art style and employs dark humor to address serious topics, making it both entertaining and thought-provoking for viewers.