In year 1961, Oshima Goro was a janitor at an elementary school in Narashino City, Chiba Prefecture, where he started a private studying session. One of the students studying there was Akasaka Fukiko, a daughter being raised by single mother Chiaki. Chiaki decided to approach Goro and proposed about opening a private tutoring school together. The couple later got married and opened a private tutoring school near Yachiyo City.