Nikki Sixx and Courtney Bingham, his girlfriend of two years, have become engaged over the weekend.
"I'm so excited to share with you that @NikkiSixx and I are engaged!!!!!!" Bingham posted on Twitter Monday. "Thank you for all the kind wishes!!! Xoxo."
"@CBingham and I wanna thank you all for the beautiful congratulations on our engagement," Sixx also added to Twitter. "Were beyond happy and in love."
The pair also shared on Facebook: "We would like to thank everybody who has been tweeting and posting online us congratulations. Both of us and our families are beyond happy."
The bassist for Motley Crue proposed to Bingham while on vacation in St. Barth's just after a romantic dinner and a moonlit walk on the beach, according to Digital Spy.
The model has since been spotted flaunting her engagement ring.
Sixx, 53, presented Bingham, 27, with what is believed to have been a 6-carat diamond ring, according to TMZ.
The model was photographed shopping near their home in Calabasas, Calif. earlier this week while wearing the impressive sparkler, the Daily Mail reported.
It will be Sixx's third marriage. His 7-year marriage to Playboy's Brandi Brandt-he shares three children with her - ended in 1996. Sixx also shares one daughter with ex-wife Donna D'Errico, who he broke up with in 2007.
The bassist has been romantically linked to celebrity tattoo artist Kat Von D as well as actress Denise Richards in the past.
Sixx founded Motley Crue alongside drummer Tommy Lee, and they were later joined by lead guitarist Mick Mars and Vince Neil. The heavy metal band is best known for their songs "Girls, Girls, Girls" and "Kickstart My Heart," among many others.
The band has been deemed the World's Most Notorious Rock Band and has sold over 80 million copies worldwide.
Last year, Tommy Lee announced that the group was working on their 10th studio album.