: The episode centers on Ai Kitora demanding that Osamu be punished for his unauthorized use of a Trigger based on strict Border rules. This "on paper" regulation is a major plot point, as Kitora values the hierarchy and official protocols of the organization.
: While broadly discussed in the series, Yūma Kuga has referred to human money as "just paper". This highlights his perspective as a Neighbor who finds human currency and social structures confusing or trivial. World Trigger Episode 4
: At school, bullies are seen throwing paper balls at Yūma's head during class, attempting to provoke him before they are eventually humiliated. Episode 4 Summary : The episode centers on Ai Kitora demanding