Justin's date speaks out!

Justin Timberlake's date to the Marine Corps Ball is talking about their big night.

Combat instructor Kelsey De Santis, who invited J.T. to the shindig via a YouTube video, says, "It was wonderful. A really good experience."

She says when she first laid eyes on the star in his tux Saturday, "He had a really big smile on his face, and so did I."
After the ball, Justin wrote on his blog, "What I didn't know was how moved I would be by the whole experience."