The Salary of a Children’s English Teacher in Japan?

How common is it for a children’s English teacher to earn 1,000,000 yen per month in Japan? See HelloWork 求人番号 13040-62219371, 株式会社 SK Global in Japanese (The author of this blog has been involved in business with a different SK group in the past). If it ever turned out that some job advertisements or job sites include deliberately inaccurate, misleading, deceptive, harassing or privacy-violating material, would it be an alleged or self-declared government’s task to get the offending companies out of business and prosecute their management?