Anybody here gone out with bf or gf and attracted to any other person?

I agree with you. I've actually discussed attraction to other people with my ex. For example we were at a restaurant and our waitress was really cute. We would joke around and he'd say something like, "I'd do her she's a cutie" to which I would reply, "Me too."

At the same restaurant there was a waiter named Sean who his mother was flirting with when we all went out to dinner one day and he always use to bring him up when we went there.

He's even told me a conversation he had with one of his coworkers about another cute girl coworker. It's totally harmless and we both knew what was too far and if either was uncomfortable with something we'd let each other know.

For example we use to work at the same company and there was a new (guy) employee who got hired during the summer. He had a crush on me but also playfully flirted with everyone at work, it was his personality. My ex wasn't comfortable with it and he told me and wanted me to clarify that point to the guy so he'd stop flirting (he didn't mind me talking to him, just him flirting with me) so that's what I did.