I have a chio colleague who always wear loose-fitting/low-cut and like to bend down showing her well-defined breasts asking me go lunch with her all the time.
Is that sexual harassment ?
In my workplace, the answer is yes.
If you stare at her tits, she can accuse you of inappropriate behaviour. There should have a office attire rule requiring women to wear bras for work safety reasons. And no kitten dresses for office please.
Also, if you lunch often with the same woman, and she is angmo, it is OK to greet her with a hug. If she is Asian, she can accuse you of inappropriate behaviour because hugging is not part of Asian culture. But the same Asian woman can hug or receive hug from the angmo male because it is part of his culture.