"Saturdays are special to us, because our first date was on a Saturday and we have celebrated with a toast, a visit to a beach, special date, a motorcycle adventure, or a road trip on every Saturday since," Inaba, 48, told People. "So on Saturday, we returned to the place of our first date and got engaged at the same place we shared our spontaneous and magical first date."
It was on that beach that Derringer proposed with a ring by Jean Dousset.
"I then got down on one knee under what I will always remember as the most serene and tranquil night sky I've ever seen and asked my beautiful girl if she would do me the honor of being my wife, to which she thankfully replied yes," the 49-year-old actor told the magazine.
While the couple, who met earlier this year, have yet to set a wedding date, according to People, they have decided to say "I do" on their special day, Saturday.
Inaba isn't the only member of the DWTS family getting ready to walk down the aisle.
ET caught up with Inaba's fellow judge, Julianne Hough, last month, where she revealed that she's already set a date for her wedding with her fiancé, NFL player Brooks Laich.
"We both want small and intimate, but I come from a very large family, so as small and intimate as it can get with my big family," she revealed. "We've been so blessed and so fortunate over the years that we've met so many incredible people in our life. We want to share it with them too."