In episode three of The OG Chronicles on OprahMag.com, the two pals discuss a range of topics, including what they'd do if they caught a best friend or sibling getting romantic with an ex-boyfriend.
The question came from a female fan, who revealed she had secretly been texting her sister's ex and developed something "really special" with him. Winfrey and King agreed that that's a line one should never cross.
"Stop it now!" Winfrey suggested. "Wow. It breaks the girlfriend code."
To better explain why they feel that way, the two put themselves in the situation. King told her bestie what she should do if she ever catches her with Winfrey's longtime love, Stedman Graham.
"If you ever catch me and Stedman boinking around, fooling around, or you catch us in bed... [you] shouldn't even be mad at me because [you] should say, 'I've lost my mind. Take me to the hospital!'" said King.
See more from their hilarious discussion below:
ET exclusively spoke with the duo aboard the Holland America Line ship for Winfrey's Girls' Getaway Cruise back in February, where they spilled a myriad of personal details. The ladies discussed everything from what they do when they see a friend wearing something they don't approve of to what they wear at home when the cameras aren't around.
Winfrey, who attended the Duke and Duchess of Sussex's royal wedding last May, also offered up some amazing advice to single girls who are looking to find their "prince," just as Meghan Markle did with Prince Harry.
"I say this: 'You have to be your own best girlfriend first,'" she said. "That's what I say to my girls. A lot of them, I say, 'You're not ready to have a boyfriend because you can't be a girlfriend to yourself yet.'"