Hugh Hefner's secretary of over 40 years, Mary O'Connor, has gone to that great Playboy Mansion in the sky. And the sassy den-mother, who saw scores of playmates bounce their man-made boobies about, will be missed by not only Hef, but by the plasticine ladies who knew her.

Hefner announced the sad news via Twitter yesterday (Jan. 27).

According to Hefner, O'Connor was instrumental in reuniting him and his new wife of almost a whole month, Crystal Hefner (nee Harris), after their failed engagement in 2011. But Mary was best known for her appearances on the reality show 'The Girls Next Door,' in which she provided hilarious side-commentary about the goings-on in the Playboy Mansion.

And thus, O'Connor's playmate friends tweeted their goodbyes in the traditional 21-tweet salute.