Some people see the ero-manga scene simply as a different genre of manga. Join up a team and work on 4-5 more projects, and you're essentially numb to it subconsciously. It's just like any other kind of manga at that point. Hell, look at some of the stuff that gets serialized.
The only difference from stuff like that and the ero scene is they don't physically include the genitalia. Compare some of those works to something from a well known plot based artist like
Homunculus or
Napata. These are artists that can work magic into a 20-25pg work that 99% of mainstream artists can't even come close to. I'd personally recommend reading
this work here by Homunculus and then come back and tell me that the ero-scene is simply porno manga.
-Tech