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On physical examination day, many of the girls are feeling stress about their weight, measurements and fitness. Nozumu distracts them by deciding to judge the "social worth" of students so that they will know whether they are living "above their station." Kitsu seizes on this idea, scolding everyone who possesses any luxuries, appalling Nozumu to the point where he decides to go on a hedonistic binge before killing himself. In the second half he encounters some of his students at a hot spring and is frightened to learn the spring has the power to remove their "toxicity" giving them well-adjusted personalities.
Episodes
1Sayonara, Zetsubou-Sensei 2When I Came Out Of The Tunnel It Was White 3Go Fly Over That Country 4From Elbow to Knee 5Removing Toxins and Stains 6Leap Before You Look 7One Morning, When Gregor Samsa Awoke, He was Carrying a Portable Shrine 8I'm a Social Outcast by Fate 9The Evening Primroses on Fuji are Wrong 10You Mustn't Burn the Raw Yatsuhashi 11That's Impossible Isn't There an Original 12What an Incredible Bother!