>>2821747Since the source is a light novel, the creator is just a writer. The official artist of Haganai's LNs, buriki, hasn't done any lewds I've ever encountered more extreme than this one.
The author's other work I'm familiar with, A Sister's All You Need, had lots of lewd art done by Kantoku in the books, but no nipples, even in Kantoku's collected artworks book after the series finished (he had uncensored versions of art from Hentai Prince and the Stony Cat in that art book, for example, so this was disappointing)