Katy Perry Rejects Fan’s Marriage Proposal, Says She’s Dating Someone Else

Katy Perry‘s staying loyal to new boyfriend Justin Trudeau … because she cited their relationship when a fan at her concert asked her to get married.

Check out this fun clip from KP’s “Lifetimes” Tour show in Prague Thursday … a fan in the crowd has a sign asking Katy to marry him and he’s even got a ring in his hand.

Katy’s response … “No, I’m dating someone else!!!”

The man courting Katy should hardly be surprised … she made the budding relationship with Justin official earlier this week, when they went out for a date in Paris, France, to celebrate her 41st birthday.

Justin, the former Canadian prime minister, has now made it into Katy’s inner circle, and earlier this month, we showed you photos of Katy and Justin packing on the PDA on her yacht off the California coast.

The lovebirds first sparked dating rumors back in July, when they were spotted on a dinner date in Montreal, and then followed that up with a stroll through Mount Royal Park.