Oh, I completely agree, there are absolutely great narratives out there where the protagonists are villains, evil, irredeemable, scumbags, etc. And those are fascinating! American Psycho also comes to mind. I guess my point wasn't that the protagonist has to be a good person, it was just a poorly-written first page in which we are immediately introduced to a guy whose only identifier is that he's a cheater. "Frank looked around, scouting out the women on the street with a grin. He'd told Rita that it was a boys' night out, absolutely no women, but that wasn't true. But what Rita didn't know what wouldn't hurt her! In fact, it might even bring them closer, such as when he cheated on her last year with that redhead from the convention. Ah, that had been a good lay. The redhead had had breasts like avocados, her nipples dark and large. What was her name again? It didn't matter. He'd find a new one tonight. And Rita would never have to know."

Something like that. As a first paragraph, I just didn't think it was a good introduction to the character or a good hook to get people invested in his story. He was given no identity or character beyond his cheating and I guess my point was that "cheating" is either a deterrent from getting really attached to the main character right away, or at best, it's a "meh". Especially when it's clear that this is ALL the story is going to be about. Some dude prowling around cheating on his wife, with nothing deeper. (Sorry, I'm projecting because a lot of the stories we've gotten lately have been like this. Guy (or girl) is immediately introduced as a cheater, then the entire story is just about his/her remorseless cheating exploits and some heavy-handed smut. Reads like someone's fantasy... I'd write more about how terrible the later sex scenes were in this story but that isn't what this post is about!) Edit: Sorry, I went on a complete rant, sorry!!!

And yeah, my suspicion is that my coworker has been harboring feelings of guilt but kept telling herself that she was justified and pushing those feelings away. I think hearing that "no one likes a cheater" hit a nerve. But you're right, I was trying to discuss fiction in the way that we always discuss it at work, this just happened to be the topic of cheating rather than something else. Thanks for your input!