Hugh Hefner knows what his young girls love, and if Crystal is a Little Mermaid kind of person, then a Little Mermaid music box it shall be.

The Playboy mogul proposed to Crystal while they opened Christmas presents at the Mansion. Hef wound it up and had Crystal open it. Instead of saying 'will you marry me?" he said "hope it fits". The ring didn't fit but they had it resized and she is wearing it now.

As for the surprise, Crystal said she knew it was coming because they had talked about getting married. She even picked out her ring with Hef's longtime secretary Mary O'Connor.

According to EOnline:

"I picked out the diamond with Mary," Crystal said. "It all happened so fast and we're happy. Nothing's changed. Everything is the same."

It's a round diamond, a little over three karats and is on a platinum setting with diamonds that go around the whole band. Crystal tweeted a pic of the ring last night.

They are hoping for a summer wedding. She wants something small and intimate with "close friends and family." Crystal wants to design her own dress. And, yes, the big day will take place at the Mansion.

Crystal also says they have no plans to start a family. "I've never really been the wanting children type," Crystal said. "I just have a bunch of different projects I'm working on and that's fun for me so that's what I'm going to do."

As for family reaction, she said, "Both my parents are super supportive of everything and whatever makes Hef and I happy makes them happy. I couldn't be happier."

What about a prenup? "Whatever Hef wants me to do," Crystal said. "I'm happy. I have the singing thing going for me and other things so whatever he wants. I don't know anything about that stuff. I don't care. Whatever."

Whatever, as long as you can live a life of luxury. I wouldn't bother either. Great catch Crystal!