Kuromajo-san ga Tooru!!

Ms. Black Witch's Sports Day (Part 2) (1x18)

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Come Sports Day, after Gyubid casts an unknown spell on her, Chiyoko spots Angolmois speaking to another man, Count Leonare, about the purposed ritual, learning the truth that perfoming the ritual will not help Suzuka's brother. Before Chiyoko can warn Suzuka, Angolmois uses paralyzing magic to prevent her from interfering with the ritual which Suzuka begins to perform atop a human pyramid. However, the ritual fails as Suzuka's magic had mysteriously disappeared. As Suzuka's brother's operations goes smoothly, Chiyoko learns from Touka that Gyubid had used a forbidden magic to sever Suzuka's pact with Angolmois, the punishment of which is becoming trapped in a tree in the Spirit World.