Nishioka is a good looking and friendly guy who is one of the editors at the Dictionary Editorial Department, before he gets transferred to the PR Department. When he first meets Majime he thinks that the latter is weird, but when they start working together they come to realize that their individual strengths compliment each other. They eventually become best friends.
After the time skip, it is revealed that he has become the chief of the PR Department, and that he regularly tries to help out the Dictionary Editorial Department to make "The Great Passage" a success.
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