...but your disagreement about what netorare is,
is firstly with a Japanese person.
There shouldn't be any consternation about her insistence, then, because you would understand that she has a different understanding of the
Japanese term denoting a concept
formulated and entrenched in Japanese pop culture.
Not that this is a difference caused by the way Americans have appropriated Japanese pop culture terms: by most accounts, there's agreement on the matter. Whether according to
dictionary.com,
TvTropes (please forgive me),
KnowYourMeme (which also reports the likely origin of the term in otaku culture),
japanesewithanime-- they say the same thing. When it's used in jokes in manga, it relies on the reader having the understanding that a concept similar to cuckoldry (meaning the concept requires
infidelity) is being referenced.
VNDB has broader guidelines than the ones I'm familiar with (that account for close associates and relatives), but they still don't coincide with your desired usage on account of its third and fourth prongs (they're not close, we see her hating him prior to her mixer, we haven't seen jealousy from him, and there's currently no apparent
cause for jealousy from him). Even then, it considers netorare a subcategory of infidelity, but with the focus on the maelstrom of emotions associated with it.
I'm not "defending" it-- "defense" isn't necessary, since it's not any more "sinful" than any other hentai genre. I didn't even take the mangaka's insistence into account when I came to my own conclusion.
I'm not "simply" not considering it netorare-- I'm appealing to the popular definition of it, and the very origin of the term. I've even produced a source with broader guidelines than the ones I've been arguing with, and this still doesn't make that cut. How many more definition sources do I need to make my point?
This manga is certainly
something. It doesn't need to be pegged with "netorare" before one knows they don't like it, but it just isn't netorare by any established definition of the term.
I'm not sure why the original plan had to be revamped to this extent because management didn't like the incest attribute-- surely, a simple 義 would have sufficed to make it kosher.