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Corina (Japanese: チヅル Chizuru) is a character of the day who appeared in Strategy Tomorrow, Comedy Tonight!. She was a patient at a Kanto children's hospital.
Ada's Chatot had been disappearing throughout the day and would return at night. Unbeknownst to her, Chatot had been visiting the hospital and cheering up the children. It took a particular liking to Corina after she offered it some cookies.
Corina threw a tantrum after Ada revealed that she and Chatot would be leaving for the Comedy Grand Prix in Johto. After sulking, Corina joined the other children as Ash, his friends, and Ada performed for them in a farewell comedy performance. While she hoped that Chatot would stay at the hospital to continue its entertaining mimicry, Corina came to an understanding. She wished Ada farewell and all the best, even giving a box of biscuits for Chatot. The gesture was greatly received, as it bolstered Ada's confidence and gave her a new motivation to pursue a career in comedy. In return, Ada promised that she and Chatot would return to see Corina at the children's hospital to perform again.