So, I took a look around the author's Ci-en announcements, and that's what I managed to find about NoR's DLC:
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, made before the game's release, author says that he would like to add more post game content shortly after the game's release.
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, made shortly after the game passed dlsite's censor check hell, he specifically mentions wanting to add more Vendetta (the white-haired girl from the base) content, and specifically mentions that he's already working on at least one sex animation/drawing. He also expressed interest in making more porn games and a side-scroller RPG without porn.
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, made after the game released, outright confirms that the author plans to add both more game content (new dungeons, high-difficulty bosses) and more sex content (again he specifcally mentions more Vendetta content).
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that specifically mentions NoR's development. In it, the author says that his health is slowly improving after the dlsite's censor check hell which fucked him up pretty badly, and he mentions that he wants to take a breather (most likely from NoR) by developing a different game.
That's kinda it for the official information. Personally, I think, and hope, that he will make a DLC/additional content someday, considering that he was very interested in making more content for the game before his health plummeted down, and he consistently made posts on twitter, thanking people who bought the game almost everyday (unsurprising, considering that the game was selling like hot cakes.) and I don't blame him from wanting to take a breather from NoR, considering that he was developing this game for 5-6 years.
