In a previous chapter someone said something like "it's always the library girls." There's a good reason for that. They typically read a lot so are exposed to a lot more of that kind of stuff. I just hope if they do do the deed we'll get a clear answer and not just a subjective let the reader decide thing.
Yes that is why in my opinion, they should just let him make some hentai works on the side.
So that HOPEFULLY that would let him release those urges over there and not on his main stories.
Letting a popular artist do hentai is probably a bad idea. Hentai artists who break into tame stuff often have trouble down the line because of thier previous hentai content. There's even a game that got banned on steam because the creator also draws hentai even though the work being published wasn't actually hentai.
That being said I'd read the hell out of any hentai the artist brings though.