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why were they shocked??
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Re-read the previous chapter, here in this scene:
http://www.mangago.zone/read-manga/dos_obake_ga_nekasetekurenai/mf/v01/c002/9/
Glasses guy (2nd pairs uke) is the same guy as the train ghost that tried to top yuuji (the 1st pairs uke)
Looks interesting