Sayonara Zetsubo Sensei revolves around a very pessimistic high school teacher named Nozomu Itoshiki who tries to hang himself in a cherry blossom tree one day, but is saved by a very optimistic girl known as Kafuka Fura, though her real name is unknown. She proceeds to go as far as to give Nozomu a nickname, "Pink Supervisor", and even offered to pay him fifty yen to do so, which he outright refused. After having enough of the strange girl, Nozomu bolts to the school, and starts his homeroom class, but finds that the girl is one of his students.