[There is a long, long pause before Joshua turns his attention to Mob, and for the first time, his expression is a little more serious rather than continuing to play coy.]

... I don't know, and that's what I want to check: one of the spirits mentioned that name, unsure if they had been truly exorcised from your city, or that they may have snuck in under the cover of the other spirits that migrated here. And if there's anyone that I don't want in my city, it's that one.

[Because even Joshua doesn't like rumors he's heard about that particular one. To think that people thought we were bad sometimes...

He then turns his attention back to Reigen as the teenager then gestures to the Scramble Crossing.]

The Underground is our name for the plane of existence that separates the dead from the Real Ground, or the living if you prefer. The only real difference between the two is that the dead can't be seen by the living, but otherwise, it's appearance is exactly the same. That traffic crossing isn't any different than it is to you, and only a very powerful spirit or Noise could change the appearance of the Real Ground from their place in the Underground.

... As for the second part of what you said, you are only half right. I'm not "possessing" the human body of another.

[And here, he smiles again, but it doesn't quite reach his eyes.]

This is very much what I looked like the day I left the living for the Underground, Reigen-san.