The 36-year-old rapper proposed to the reality star on Monday, which was her 33rd birthday.
Demi is glad he made the occasion a great surprise for her good friend otherwise she would have had to hunt him down.
Demi joked to E! News: "I've told Kanye before that if he doesn't treat her well, I'm going to come after him.”
The X Factor USA judge was impressed Kanye organized having a baseball stadium to themselves in San Francisco, California and hired an orchestra to hand over the 15-carat diamond ring by Lorraine Schwartz.
Kim is apparently so kind for helping her through emotional problems that should get nothing less than extravagance.
The former Disney star said: "I've known Kim for years and she's been such a good friend to me during some really hard times. She deserves that Giants stadium!"
Meanwhile Demi has been linked to her former on/off beau Wilmer Valderrama for some time now, but neither have spoken out about it.
However, it appears that it was a case of 'actions speak louder than words' when the pair were spotted holding hands recently.
With Halloween just around the corner, Demi and Wilmer got together to visit Berry Farm's Halloween Haunt and they did a good job of just blending in with the crowd as Demi dressed down in a pair of ripped black jeans, a black tee and a black hoodie which she wore up, covering her hair.
