> Even if it's consensual, what happens when she decides she wants to move on from the relationship?
Then they're no longer in a relationship and still have to follow HR/company policies.
>What about her peers that didn't receive promotions while she did?
Did they follow the company policy (e.g., hiring committee recusal) or not for the promotions?
>This is why these laws exist.
Did the company policies follow employment regulations when setting and enforcing their policy?
Anyway, not sure if that's the case here but it's hard to rule out entirely.
These policies are intentionally narrowed to workplace conflicts of interest. HR doesn't want to manage morality clauses or stuff outside the workplace.