When you get off at Shin-Okubo and turn right will see the street that similar walking at Korea area. This area most people call in Tokyo as Korea Town. This is located in Shin-Okubo, near Shin-Okubo Station, on the Yamanote Line (JR). It’s close to Kabukicho, Waseda University and Takadanobaba.
The street is like walk to Korea shopping street.