Genryuusai is a master at the WNA Academy.

Set in the year of 20XX, the series focuses on a group of 9 young rookie ninjas, called the Ninja Gum Kids, who are descendants of ninja clans who have mysteriously disappeared. The Ninja Gum Kids want to achieve one goal: to become master ninjas.

Shigeru Nagashima, known professionally as Choo, is a Japanese actor, voice actor and narrator. His former stage name was Yuuichi Nagashima, he changed his stage name to Choo on August 23rd, 2006. He is a graduate of the Nishogakusha University Department of Literature and received training at Bungakuza's research establishment and the Seinenza Theater Company before attaching himself to Production Baobab in 1986. He transferred to the Tokyo Actor's Consumer's Cooperative Society in 2007.

Choo's hobbies include badminton and jogging, and he is a licensed calligraphy instructor.

(Source: Wikipedia)