Gene Simmons, who has vowed in the past that he would never get married, pops the question to his longtime girlfriend Shannon Tweed on tonight's episode of their reality series 'Family Jewels.' The Kiss singer-bassist and the actress/model have been a couple since the '80s and have two children together.

In a video preview of the show, Simmons can be seen on a beach in Belize proposing to Tweed as he gets down on one knee by the seashore.

"I come with so much baggage, but you're the only friend I've got," Simmons tells Tweed while standing and holding her hand. "You're the only one I've ever loved. You're the only one I love and you're the only one I ever will love, and I will say those words to anybody."

With Tweed gasping, he kneels down and says, "Please marry me." We'll find out tonight if Tweed says "Yes."

'Gene Simmons Family Jewels' chronicles the everyday life of Simmons and Tweed, along with their two children -- 22-year-old Nicholas and 18-year old Sophie. Tune in tonight (July 26) at 10PM ET on A&E.

Watch the Preview of Tonight's 'Gene Simmons Family Jewels' Episode