Leighton Meester Is A Runaway (Royal) Bride! [PHOTOS]

And she isn’t coming back!

Leighton Meester ran through midtown Manhattan last night in a strapless ivory wedding gown and a glittering tiara atop her head.  Meester’s Gossip Girl character is due to marry Prince Louis of Monaco in the CW show’s 100th episode.  Though no plot has been given away just yet, it’s sure to be sensational.  Blair is torn between becoming Princess of Monaco and running back to the love of her life, Chuck Bass.

PHOTOS: Blair Waldorf Gets Taken Away In Handcuffs!

GG fans knew this day would come, when Blair would run through traffic on the biggest day of her privileged life.  “Take me to JFK,” she screamed at the driver.  I totally made that up, but it’s a good enough guess.

No doubt Serena’s dress is full of cleave and trollopness.