Justin Timberlake parties with elated U.S. Marines as promised

Justin Timberlake accompanied U.S. Marine Cpl...

Justin kept his promise to attend the dinner and party

Justin Timberlake is a man of his word. The superstar made good on his promise after accepting a YouTube invitation to attend the Marine Corps Ball on Saturday night in Richmond, Virginia.

The singer-turned-actor fulfilled his promise and arrived on the arm of U.S. Marine Cpl. Kelsey de Santis, who asked him to be her date in a YouTube video.

Timberlake looked dapper in a black suit, white shirt and a snazzy bow tie as he made a grand entrance into the Greater Richmond Convention Center.

According to local television station WTVR, the wife of one of the marines at the ball said Timberlake 'posed for pictures and seemed like a normal guy'.

His Friends with Benefits co-star Mila Kunis was invited to the November 18 Marine Corps Ball in Greenville, North Carolina.

Sergeant Scott Moore made a YouTube video asking Kunis, 28, to be his date to the gathering.

Her spokesperson recently told The Washington Post the Black Swan beauty is still planning to attend.

After Timberlake encouraged Kunis to accept the invitation, De Santis invited the Sexy Back singer to a Marine Corps ball via YouTube.

'So, Justin,' De Santis said in her video clip. 'You want to call out my girl, Mila? Well, I’m going to call you out and ask you to come to the Marine Corps ball with me on Nov. 12.'

She even added a reference to one of his songs: 'And if you can’t go, all I have to say is cry me a river.'

The annual event is a hot ticket for U.S. Marines, but is not open to the public.

Those attending must be active duty Marines, reservists or retired, although they are allowed to be civilian guests.