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(Yahoo!) - Is Katy Perry trying to drop a not-so-subtle hint?

Sunday at the MTV European Music Awards, the "Roar" singer stood out on the red carpet in a figure-flattering mint Zac Posen dress, which she paired with a Dolce & Gabbana headband and Charlotte Olympia heels. But all eyes quickly shifted to that finger because she was also rocking a suspicious diamond ring.

The 29-year-old — who is head over heels for her musician beau John Mayer — worked that ring. She posed with that hand artfully placed on her hip as if to display it for the world. And she was glowing — though it's unclear if it's that of a bride-to-be or the "Prism" star's typical radiance. Let's face it: She's a pretty radiant gal anyway.

While reps for the couple haven't yet responded to omg!'s request for comment, KatyCats were buzzing over the very idea on Twitter.

Though not everyone was head-over-heels about Perry, whose marriage to Russell Brand was brief and whose divorce was very painful, heading down the aisle so soon.

If this isn't an engagement ring, don't be surprised if things head that way — and soon. Together since 2012 (they weathered one brief breakup), Perry gushed about her rocker boyfriend in the November issue of W magazine.

"I actually am dating my crush," she said. "I had a crush on him for a long time."

In the same interview, she said she "loved" being married, calling it, "a new, fun, exciting journey." But she added, "I think all things happen for a reason."

And in an interview with Billboard in September, Perry went so far as to call Mayer a "genius."

"I always tell him, 'Darling, you know I'm going to have to give your mind to science after you've passed, because we're going to have to understand how all these sparks work,'" she said.

So it sounds like it's not a question of if, it's a question of when the engagement will happen … if it hasn't already.

Do you think Katy and John are engaged? 

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