Makaino was born in the city of Toyohashi, in Aichi Prefecture.
His father Noboru was a music-lover and amateur composer, and he got Kōji to become familiar with musical instruments.
After graduating from Aichi Prefectural Commercial High School in Toyohashi, he studied music at the Naomi College of Music before dropping out in 1967 join a group called "Blue Sharm."
He has worked under the pseudonyms Mark Davis, Jimmy Johnson, Michael Korgen, from the fact that since the late 1970s, many foreign artists have been hired on TV CMs, and because he wanted to show he had a foreign style in some ways.
where Makaino has been credited for the soundtrack: Listed by the year they started airing.