Yasuda Taisei

Proprietor of a new knickknack shop in Udagawacho.

While he was wandering along the JR tracks picking up lost and abandoned items, Achi foisted off his trash onto him, and so he's in a bit of a foul mood.
Yasuda watches roughly 350 martial arts fights a year. He is particularly fond of Brazilian jiu-jitsu, and is thinking about studying himself. There's a dojo he's been eyeing, but he's rather timid, and has thus far only waffled noncommittally outside the entrance to the place.

Achi knows Shibuya like his own backyard, but Yasuda is new enough that Achi doesn't recognize him.