Britney Spears Walks Backstreet Boy Howie Dorough on a Leash During Las Vegas Show

Britney Spears has always been thought of as an NSync kinda gal, thanks to her relationship with Justin Timberlake, but she was a fan of the Backstreet Boys too.

The singer proved it by summoning Backstreet’s Howie Dorough to the stage during her “Piece of Me” show Saturday at Planet Hollywood in Las Vegas. Spears herded Dorough with a whip — while he was on all fours — during her rendition of “Freakshow.” They’ve come a long way since the days of her schoolgirl uniform and BSB’s cheesy matching suits!

And what is it about ’90s pop stars checking out each other’s shows lately? (Other than the convenience of not having to leave Las Vegas to do so — the city is chock-full of artists who were tearing up the charts roughly 20 years ago.)

Just last month, former NSync-er Joey Fatone stopped by the Backstreet Boys’ own Planet Hollywood show, “Larger Than Life” and, after being pulled onstage, planted a kiss on Nick Carter. After all, it’s been a long time since NSync and the Backstreet Boys were radio rivals.

Another night last month, Lance Bass (NSync) checked out the Boys’ show and ended up singing their hit “Shape of My Heart” alongside Carter.

It’s your move now, 98 Degrees.

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