The manga industry has been around for far longer than many fans realize, and it wasn't always ruled by many of the tropes and archetypes that now dominate it. Various genres with just as many intended demographics existed in the past, with one theoretically being a different medium entirely. Said medium was exemplified best in the series that's the oldest manga still in publication.
Source：https://www.cbr.com/golgo-13-noir-action-inspired-mature-manga-gekiga/
