Stick to your lane, there’s a reason they confided in you in the first place. They trusted you to keep your mouth shut.

If the relationship is purely something your coworker told you in confidence, and you have no evidence of favoritism, coercion, retaliation, or policy... violations, many people would choose not to insert themselves into a private relationship. more

If the relationship is purely something your coworker told you in confidence, and you have no evidence of favoritism, coercion, retaliation, or policy... violations, many people would choose not to insert themselves into a private relationship. more

If the relationship is purely something your coworker told you in confidence, and you have no evidence of favoritism, coercion, retaliation, or policy... violations, many people would choose not to insert themselves into a private relationship. more

The good part of your narrative is that your coworker confided in you meaning he/or had confidence in you. To me I would advise you to keep it as... secret between you and them. Confidentiality is one of the work ethics. My advise. more

Just get to work, do your job get paid , go home ! Simple.... Don't get involved in things that wont pay your bills at the end of the day

Report what? And what outcome do you intend to achieve? Those are grown adults. Also, the worst thing you can do is break the trust by discussing that... with someone else. Just don't
Keep it to yourself. more

I wouldn’t report someone simply for having an affair. But if the manager has authority over this employee’s promotions, bonuses, evaluations, etc.,... there’s a legitimate conflict of interest. I’d stay away from gossip and only raise it with HR or an ethics office if you have reason to believe there’s favoritism, retaliation, coercion, or a violation of company policy. Report what you actually know—not assumptions about what may be happening. more

This risky. Guide co worker to stop because they may get fired instead of promotion. I hope you get

And how does this affect you?

What exactly would you be reporting, the illicit relationship or the promotion and bonus speculation? The only 'fact' that you have is the confiding... in you by your coworker, about the manager coworkers illicit relationship. This now becomes a confidential matter that must be handled very carefully. Your primary duty of care, is to continue to be an ear for your coworker, and if you are one of moral principles, guide them away from such a relationship. If the coworker subsequebtly confides that they were forced or threatened with lost of their job, if they did not get sexually involved with the manager, then you would have a legal duty to carefully address, and in the interest of your word against mine, get the coworker to find a way to provide evidence of that fact. Your mentioning of the promotion and bonus remains speculation until you hear directly from your coworker on this specific area. Until then, it is just a moral issue to address with your coworker.  more

If there is a non-retaliation policy in place .. Talk to your coworker , if she confided in you this may be a cry for help. However , if there is not... a policy in place mind your own business. Managers have power , and control … more

Don't ever involve yourself in another person's cheating scandal. It might be tempting to tattle on the two, but please mind your own business!

Once you start referring to a worker as 'they', you are wasting my time. The worker, if human, is either 'she' or 'he'.

Stay out of it because your getting paid to work so protect yourself

Stay out of it makes sense...unless

But it may have something to do with the writer. Such relationships can actually distort business performance.

I would talk to the co-worker. Let them know that it's risky behavior ( mainly for the manager) in that should that manager in fact do something that... seems like favoritism or otherwise un- impartial treatment of her, being in a relationship with him, could constitute a " quid pro quo" sexual harassment claim. These claims are serious and often come with more consistently negative consequences ( for the manager involved).The " optics" alone can trigger such a claim. more

Protect your job by minding your own business

i agree you dont wanna get in trouble for something that has nothing to do with you