It's her daughter from a previous marriage how exactly is that NTR?
Cause she was fucking someone else than her future husband... isn't that obvious?
To be serious for a moment, it isn't, but that is how dudes tend to think... like you do get memes like this:
Anyway, I think the thing that rubbed people the wrong way more, was the deception, and the NTR comments just spawned from that.
Men sell their experience. Women sell their purity.
And her deceiving MC pre-ruins most if not all of the potential purity factor going into the game. (like if she lies about that what else would she lie about?)
Now I'm not saying she isn't a saint, she well could be (well... a little bit, not completely that ship sailed
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). But that is the expectation it sets up. (There's a reason the first comment is what it is...)