Zan Sayonara Zetsubou Sensei Bangaichi

懺さよなら絶望先生 番外地

Despair follows Nozomu through a zombie invasion of bad ideas, the way people laugh at things they don't understand, going with the flow, and more in this sequel to Zan Sayonara Zetsubou-sensei. Also continues the use of numerous puns, inside jokes, and discussions through background text and signs.(Source: Anime News Network)