Doraemon (1979)

Life Rescue Plan (15x20)

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Nobita and Doraemon travel back to Nobita's kindergarten days so that Nobita can give a young Gian and Suneo their comeuppance and stop their bullying. However, this causes a younger Shizuka to hate him and now Nobita must make a decision between stopping Gian and Suneo's bullying or maintaining Shizuka's friendship.