Hugh Hefner is engaged to Crystal Harris again, in a new twist to the life story of one of the world's most interesting senior citizens.

Hugh Hefner, the 86-year-old founder of the Playboy empire, has reportedly asked buxom blonde model and longtime lady friend Crystal Harris, 26, to take his hand in marriage, according to TMZ.

The announcement comes as a surprise to those who follow Hef's dealings with the fairer sex.

Here's five things you should know about Hugh Hefner's engagement to Crystal Harris:

1. This isn't the first time he's taken the leap, as Hugh Hefner got engaged to Crystal Harris once before, and their wedding was called off just five days before it was supposed to take place last June.

2. He may want to be careful this time. Last year's planned nuptials were canceled when Harris broke the engagement and the ever-pajama-clad Hefner's heart in one fell swoop.

3. The wedding is already being planned. TMZ reports that Hefner plans to change Crystal's last name to Hefner (actually, it's unclear whether she'll take his last name) on Dec. 31, 2012. The party will go down in the famed Playboy Mansion as revelers - which TMZ said will consist of the limited number of attendees of "an intimate gathering" for just family and friends - ring in the New Year.

4. Hef and Harris are having to swallow their pride. Both of them spoke ill of the other following the end of their first engagement. Harris said on the Howard Stern show that sex with Hefner lasted "like two seconds," while TV Guide reports that Hefner said in a different interview that being single is his "natural state" and "I don't know what I was thinking about" in getting engaged to Harris.

5. Neither of the lovebirds are speaking directly to the reported plans for a wedding, but there have been hints on Twitter. Harris tweeted the following on Nov. 30: "Dear past, thank you for all the lessons. Dear future, I'm ready." Hefner retweeted the message shortly thereafter. Sounds like love's in the air at the Playboy Mansion.