I have a friend who I consider lucky to have. Her kindness, intelligence and understanding helped me on many occasions since childhood. There is just one problem; she does not understand professional boundaries and her jovial and joking manner that could be considered "cute" or "endearing" in high school is creepy, perverted and inappropriate at the workplace.
She is attracted to one of our colleagues and has no compunction bothering him in the middle of his work, lunch or any other time. She would go to him and make lewd remarks. For example, "Hey can you play with my Pooku, she'd love to see you." The poor guy thought Pooku was her niece or daughter and did not know that it meant the vagina in our native tongue.
Initially, he would listen to her blather good-naturedly, but now the problem is so bad that he cringes and stiffens every time she sits next to him. I'm worried that one day he'll decide enough is enough and complain to our superior about sexual harassment, which may result in her getting sacked without notice. I would not want that to happen to a dear friend of mine.
On more than one occasion, I warned her about this inevitability and got only careless replies from her, "You're just jealous that I'm not flirting with you" or "He likes it, just pretends not to."
Can anyone offer me advice on how to deal with this without losing my friend?
Edit: Please explain the downvotes and how I can clarify my question.