Colbie Caillat Has the Cutest 'Friends'-Related Proposal Story

She's his lobster!

How could Colbie Caillat resist such a cute proposal?!

The "Bubbly" singer said "Yes" to marrying her longtime boyfriend, singer Justin Young, late last month. Now, she's telling ETonline the story behind his romantic (and totally not embarrassing!) gesture.

"He always gets so embarrassed at how he asked, because now we have to tell this story to everyone," Caillat revealed.

NEWS: Colbie Caillat Is Engaged! See Her Gorgeous Ring

In her Instagram post announcing the engagement, Caillat declared that Young "asked me to be his lobster," referencing Phoebe Buffay's infamous "She's your lobster!" line from Friends.

"That was always our thing, we would always say that to each other," she said, "so he proposed to me in an entire red lobster costume from head-to-toe. I have pictures and he gets so embarrassed when I show it to everyone, but it's like our little thing and it was really cute!"

Caillat is gearing up to hit the road with Christina Perri for their co-headlining Girls Night Out, Boys Can Come Too Tour, kicking off July 10. But is she ready to start planning a wedding, too?

"We're super mellow and cruisey with that, so we want it small," she said of the impending nuptials. "Maybe in a year, or on the beach somewhere with the two of us."

WATCH: Colbie Caillat Goes Bare-Faced in Emotional "Try" Video

No word on whether lobster will be on the menu...

Follow Sophie on Twitter & Instagram.