Wait till you found out that:
- Masamune Shirow (Appleseed, GITS) still draws hentai artbooks
- Butcha-U’s drawing for a non-hentai manga
- Coolkyousinnjya also does hentai
- Amahara is a hentai artist too, with a very distinctive artstyle (like crayon shin-chan, but better IMO)
- Jouji Manabe does hentai.
Eh, Masamune Shirow did artbooks since the 1980s - it’s just that his perviness factor got higher over time, and he’s not known as being a hentai mangaka who went mainstream.
Butcha-U is an illustrator for the Isekai manga “might as well cheat”, although isekai mangas are a dime a dozen these days, and other hentai mangakas are known to draw for them as well - Danimaru also did a cute isekai manga involving a cat god (placed into hiatus and silently killed off) - but in those cases the mangaka is adapting a story from a light novel author. There’s a certain skillset needed to write both good hentai (tend to be mostly one-shots), and good serialized original manga - a storyline in hentai is often just a 3 page convoluted excuse to get nasty, while a serialized manga requires engaging characters, plot, pacing, etc. The irony here is that Danimaru is pretty good at the hentai plotlines (although it’s almost always a dominant gal type and a guy who is more then happy and willing to go along) - considerIng that it is essentially how
Uzaki-chan wa Asobitai plays out, you figure that he’ll have more success with mainstream serialization. Nope! Either he likes hentai stardom or isekei mangas pay better.
Coolkyousinnjya (Kobayashi Dragon maid) definitely did hentai, and the hentai was done while he was serialized as a normal manga artist, so I have no idea if he got famous doing hentai while in a doujinshi circle and transitioned into mainstream manga, or he’s a mainstream mangaka delving into hentai as a side gig. The same can probably be said about Amahara.
Jouji Manabe (of Outlander/Rin x Mama fame) doing hentai? I don’t think any of his work is explicit per-se - it’ll go into the “erotica” category rather than “mature”. His output can be lewd but it’ll probably be around the same level of lewdness as say…Nikumaru (Bad Girl/Someone’s Girlfriend).