Magimoji Rurumo

Season 1, Episode 9: A Secret I Can't Tell Anyone

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The serious student monitor Shimomura Masako loves anime and creates her own cosplay. When Masako brings her cosplay accessory to school, she drops it on the ground. Rurumo witnesses the event. Masako already feels a sense of affinity for Rurumo due to her mistaken belief that her witch's outfit is a cosplay and is moved when Rurumo doesn't mock her hobby, inviting her to a cosplay event.