What is "kogaratsu"

Kogaratsu is a comics series created by the Belgian comics creators Bosse (pseudonym of Serge Bosmans) and Michetz (pseudonym of Marc Degroide). It was first published in Spirou magazine in 1982. The success of the series, written by Bosse and illustrated by Michetz, inspired then illustrator and script writer Bosse to give up illustrating in order to focus solely at script writing.