Shin Nitta is the manager of the Card Capital car
d shop. He is an expert at many TCG's, including Vanguard. Misaki Tokura is his niece, and she usually watches the counter when he's not around. He hosted the Vanguard Shop Tournament at the Card Capital. He has a cat that he calls the "Sub-Manager", which usually results in the cat ignoring him until he refers to it as the Manager, which is Nitta's position.
Shin Nitta

Nitta's character design