4화: 소년학교 여행 중 Vertex 위기를 맞은 스미, 소노코, 진

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Sumi Washio, Sonoko Nogi, and Gin Minowa are going to their elementary school's class trip. The three of them are put in a crisis because of the Vertex's advanced action whom appeared as if to shatter their fun everyday life. (Source: Amazon)