I really don't understand how people think like this, beyond having been raised motherless I can't understand how they fail to wrap their head around the idea of Mother-Son NTR games.
Netorare at the end of the day is all about losing a relationship, damaging bonds, or many similar scenarios.
While most doujins or games makes it so the cuck/son character has an ingrained sexual attraction towards their mother, in a way that would make Freud blush. Even a normal person, not from Alabama, should understand that the bond between a mother and a son can be damaged like any other type of relationship.
Less make an example so everyone can understand it very simply.
Let's say I have a friend, who I don't particularly like as a girl, and there is this guy I HATE, because he is Suguhaphobic. Saying things like "Incest is bad" "Suguha is not even in the top 3 characters from SAO" "etc".
Of course, like any normal person I could not continue my friendship with that girl if she started dating the person I hate the most in the entire world. By choosing that relationship, she would be doing so while acknowledging that it would be jeopardizing our friendship.
(A broken bond over someone not appreciating the best girl, a tale as old as time.)
Now, take that very common place example that happens everyday in the real world, and apply it to a similar concept with your mother.
You may, or may not love your mum, depending how much she likes or doesn't like Suguha, but I'm sure that you wouldn't be able to proudly say you love her, if she spent her every weekend giving rimjobs to random homeless guys for the art of the craft.
The moment a character chooses someone or something else over the protagonist/cuck in question, be that for love or simple the pleasure of giving rimjobs to hairy hicks doesn't matter, that can be counted as NTR when framed by a porn-point-of-view.
Perhaps it's just me being old fashioned, and not as hip and trendy as Moss555 himself, but I'm pretty sure I wouldn't be able to be accept my mother fucking some random criminal, a classmate of mine 20 years her junior, or anyone who I find similarly disagreeable.
Anyways, no Suguha today, just a random Kyouko post to keep it relevant to the topic at hand.
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