So, I had to Google what NTR even was for this... I think people hate it (they're not afraid, they just hate it) cos people are hardwired to hate cheating. I mean, people like cheating cos they get a thrill out of it, but most are hardwired to hate betrayal, especially those on an emotional level. Which is ironic cos there's people out there who say they hate cheating but cheat themselves...
Anyway, people just dislike it due to societal values, we've been brought up to dislike it, so there's resistance to it. Cos who likes being cheated on? As for if I like it, I'm not a fan myself. I mean, I like the idea of going about, fucking everyone, but generally not behind my partner's back. It'd be more of a open-relationship deal for me, cheating's just not my bag.
But yeah, that's why people dislike it. That and the cheater/cheatee/both parties are often absolute cunts. I mean, honestly, I've never seen a NTR thing where someone isn't like "Oh, my husband's tiny dick won't please me! I'm glad we're fucking on his dead grandma's ashes! Go on, take a shit in the urn!". I mean, you never see an NTR where it's someone cheating on their partner cos their partner is kicking the shit out of them and they found someone who's genuinely a nice person who loves them for them (it's the only time I agree with NTR, when it's a really shitty situation. Otherwise, just break up, why bother cheating? It's just having your cake and eating it). But I think you get my point by now.
Thank god I double googled this or I'd be talking about cuckolding (NTR is apparently mistaken for cuckolding). Thankfully dodge making that mistake!