Family Frenzy Diary
The Melancholy of CHika (1x13)
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Chika goes to school, however a bunch of classmates ask her help to solve the disappearances of several classmates. Kyouka appears to help and they discover that the reason behind the disappearances was a drug developed by the mafia that turned people into animals.
In the end they are saved by a green version of Hyouka and confront the true mastermind of the plan, a experience created by the department of supernatural affairs known as Electric butterfly.