Mila Kunis and Justin Timberlake. (Jemal Countess/Getty Images)

Stars! They can be so charming when they need to be. But will they still love you when the press tour is over?

So we wondered in July when Mila Kunis, put on the spot during a TV interview about her new movie, agreed to attend a November Marine Corps Ball with a sergeant whose witty date solicitation had gone viral on YouTube. Days later, co-star Justin Timberlake pledged to attend another Marine gala with a Quantico-based corporal who had taped a copycat video request of her own.

But that was four months ago. Since then, “Friends With Benefits” — the movie they were flacking in so many winsome interviews — has opened and closed, having grossed a satisfying $145 million worldwide. Are the actors really still keeping those dates open on their calendar?

Apparently. . . yes. A Quantico spokesman told us the base has received “verbal confirmation” from Timberlake’s people that he will escort martial-arts trainer Cpl. Kelsey De Santis to her unit’s annual ball at the Greater Richmond Convention Center next Saturday. A rep for Kunis, meanwhile, told us that she is still on track to accompany Sgt. Scott Moore to his gala in Greenville, N.C. on Nov. 18.

Read earlier: Celebrity guests at Marine Corps Balls: Do the Few and the Proud know what they’re getting into?, 7/19/11

Marine Sgt. Scott Moore on why he asked Mila Kunis out via YouTube, 7/13/11