What a class act. Justin Timberlake kept his promise to Corporal Kelsey De Santis and was her date to the Marine Corps Ball in Richmond, Va.

Us Weekly reports that Timberlake accepted De Santis' YouTube invitation to the ball after encouraging his 'Friends With Benefits' co-star Mila Kunis to attend another Marine Corps Ball on Nov. 18 with Sergeant Scott Moore.

Hollywood's reigning Renaissance man was moved by the experience, writing on his website, "I've met so many of my heroes -- from Michael Jordan to Michael Jackson -- and nothing makes me feel more honor and pride than when I get to meet one of you."

Timberlake was not only in awe of the service men and women in general, but also of his date. "For a short while, I had the opportunity to sit with Kelsey, get to know her and get a tiny glimpse into what her life as a Marine was like," he wrote on his site.  "She talked about her training in mixed martial arts with a passion, a discipline, and a respect. It reminded me of how I hear my favorite athletes talk about their sport or, how I hear my favorites among my peers in music and film talk about their craft." Good thing he didn't try getting fresh -- she could probably whoop his behind!

Except she was too sweet to do that, even if she wanted to. "She seemed to me to be so humble and honest ... Very cool," Timberlake said of De Santis. "She also simultaneously seemed like she was nervous about the whole evening and if I was going to enjoy myself. 'Are you ok?' she asked two or three times. 'I hope you are having fun. I know you will once my crew of friends get here to the table.' I have to tell you, it's not every day that I meet a 23-year-old girl and she's more worried about if I'm having fun or if I'm comfortable!" Timberlake wrote. "It hit me all of a sudden that these were the type of people that look after us and our freedom ... Humble, concerned for others before themselves ... This was the type of person our Marine Corps was building. I was really blown away."

Timberlake was amazed at the Marines and the military in general after his experience. "To all of you that serve every day for us ... Ensuring our freedom, I say: My deepest gratitude to you ... Last night changed my life and I will never forget it."

Finally, Timberlake thanked his escort. (Get your Kleenex ready, everyone.)

"Thank you Corporal Kelsey DeSantis. Thank you for inviting me. And thank you for being my hero."

Watch Corporal Kelsey De Santis Invite Justin Timberlake to the Marine Corps Ball

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