
To put this into perspective, manga that sell over 10 mil typically are from established artists, are Shonen manga that appeared in the top 3 Shonen manga magazines, have been ongoing for over 5 years, have an anime, and have over 10 volumes.
O-ME-GAD! Is basically a (slightly trashy) romantic comedy. The closest manga that I could find to it is Oh My Goddess! which ran for over 10 years with 48 volumes. It sold 25 million copies. There is a manga that is still ongoing that has not sold more copies than this. And Oh My Goddess was not even close to be as (slightly) trashy as OMG lol
The manga industry is incredibly oversaturated and Sachio was lucky enough to be published in a magazine. If he has to go independent it will be even harder for him to sell.
Is 8 million copies sold not alot in this industry?
Sounds like a lot? And it's only 7 volume so each vol. had to at least sell 1 mill each.
I guess making it into an anime is sign of success like the brother in law? Or maybe it was translation error?