It's an interesting piece of work, indeed. At least, Americans had a partial edition of the manga. It never hit my soil...
Do you know Charles Baudelaire, the pioneer of morbid romanticism ? His poems can definitely be juxtaposed to DNH's intention. Old-school shoujo were all like that, with a ladleful of sadism behind protagonists relationship.
The core of this work's interest (OAV or mangas) is definitely dialogues, full of gloomy insights. Art and the rest hasn't particularly well aged, but its message still remains timeless. I would probably like a lot to learn out that there's a scanlation from Ashibe Yuho and Ikeda Etsuko's manga somewhere.
The description on MAL confused me so much, because when I started watching it, I thought I was watching something else entirely. I think the description on MAL is for the manga, and not this OVA per se?
But, I enjoyed the OVA, it was mysterious and I would've loved to see more of it.