Hope someone will indulge me on this:
When did you start knowing about ntr? When did you start to enjoy it? Was it love at first sight kind of situation?
As for me, I am not actually like NTR as concept of "stealing someone lover" etc, but I like corruption and slutty girls, and such girl having a boyfriend is nice addition to her sluttiness, like cherry on the top, same with some niche scenes that could be found there like infamous stealth sex in front of obvious cuck or sex during phone call and so on, I suppose you called it "mystery NTR" here, it's good thrilling setup when done right. Firstly I was neutral to it, was more into gangbangs, tentacles and so on, mostly looking for good artstyle, not plot points. Don't remember when started with NTR actually, maybe with [Menosuke] Birthday!! CG set and [Kumoi Takashi] Himitsu no Melody doujin (these are the most old NTR works on my HDD, so it might be the case). First one had phone sex scene and it was first time I found such thing and second one is this case of a slutty girl (with futa girlfriend) for whom one dick is not enough so she is fucking with two other futa girls behind girlfriend back. Later was famous [Jin] Tachibana-san circumstances with men series and Shinozuka Yuuji's works and so on.
Don't like netorase actually, because it feels retarded (but justified when it turns to netorare) and netori because it's hard to root for scumbag bull in most cases, but can go through it if it have good art and scenes. Also there are cases with unbearable cuck who is so annoying and clearly don't deserve girl that NTR is really welcome. And another NTR-welcome category is the man ntring yuri pair, too bad it's rare, maybe someone can suggest something like that. Also don't like when it tries to be overemotional drama, prefer it to be lighthearted or comedic even, with no heavy rape, suffering, humilation and so on. Because of all of that most times it hit or miss with me, for example I don't like much most of the games that heavily appreciated over NTR-fans, such as Scars of Summer or Raiohgar for example, these are have some good scenes of course but overall impression is meh (not to mention ugliest bastards I've ever seen in Scars of Summer, and I am even fine with bestiality genre but ugly bastards just not click with me).
P.S. sorry for the bad english, not my first language, hope this long-ass text isn't too painful to read (impying anyone would read it, hehehe).