Others have explained it, but yeah, by the strict definition of NTR, that wasn't it. Hell, you may be making a mistake addressing that question to me because I'm a bit more "assholish" about it than most people here because I'm not invested/dislike the genre so I can be more critique about it, like, I consider 99% of the SAO "NTR" that uses the non-Asuna girls to NOT count as NTR because, like Oozaru said above, you CAN'T "have stolen" what doesn't belong to you in the first place XD NTR literally means "stealing another's lover" yet over the years it's been used so much that it stretches to the point of being used in any female even remotely close to a male character.
Maybe it if actually was like your average cliche harem series like To Love-Ru where the MC never gets it on with anyone but there is still clear attraction between not only the heroines towards him but ALSO from him towards them, then I give it a pass of being considered 'NTR', but in a case like SAO where not only is the MC not interested romantically in the other girls at all but doesn't really show any real attraction towards them and is firmly and happily in a relationship, then I don't really consider the use of any non-Asuna girl as actual NTR at all and anyone who uses it to be wrong. I know many disagree on that aspect because they think that as long as SOME relationship is being "stolen", then it is NTR, but from what I think the word was created for in the first place it just really doesn't fit.
So no, I don't consider the scene in Canon Fairy Dance NTR at all, Sugou doesn't STEAL absolutely anything about Asuna in the way the Hentai Tag is meant to cause at all, like, would you label as NTR a doujin that halfway before the NTR MC did anything more than groping the Heroine has the 'cucked' one stand up, cut him to pieces, then go off to kiss and fuck with the heroine for the rest of the doujin XP? Because that's basically it. Not only is that there was no obvious NTR conclusion, Asuna expressed nothing but disgust and had not an ounce of pleasure, she found the experience nothing but disgusting and traumatic (Like, you know, she and most females would do outside the imagined NTR worlds where they're all sluts under the surface that are eternally unsatisfied with the people they like, even if the source material says they actually ARE great lovers and/or well-endowed, which funnily enough DxD, TLR, and even SAO have done XP). The 'without any resistance' part is because she doesn't want to give him the satisfaction of seeing her suffer from it, as she knows she CAN'T resist at all given Sugou basically had complete control of that world at that moment and could have made Kirito suffer worse if she did, though this last bit not only matters less but also is part (Like A LOT of SAO's nuance sadly) of the inner narrations and thoughts that the anime adaptation cut 90% of, sadly.
If Asuna showed even the slightest bit of 'positivity' towards it or even unwilling pleasure, then I would agree with you that at the very least the scene would be "kinda NTR-ish" despite its end completely negating that label, but that's not the case at all as she has nothing but the realistic reactions one would expect from it :O
This particular work is from a guy called Airuru that has been making an animation story using Koikatsu models (Same program Fujino uses for this game's models) to make a NTR story centered around Nishida first brainwashing and then fully 'stealing' Asuna from Kirito using a mix of the cliche Hypno App from Hentai and just plain out plot-convenience, it's been of surprisingly high quality and length. What Ooazaru linked there were the last bits, but here is the author's Pixiv Fanbox page if you wanna scroll back to find the whole thing:
