Justin Timberlake's Marine Corps Ball Date: "He Was a Complete Gentleman"

Justin Timberlake is America's sweetheart!

On Saturday, the 30-year-old singer-actor attended the Marine Corps Ball in Richmond, Virginia with Corporal Kelsey De Santis. So what kind of date was Timberlake? "He was a complete gentleman!" De Santis gushed Tuesday on Good Morning America.

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"I didn't know what to expect really. I was super, super excited," she said. (In July, De Santis asked Timberlake out via a Youtube video on the heels of Mila Kunis getting asked out the same way by Sergeant Scott Moore.)

Her favorite part of the evening? "As soon as the ceremony ended, not only just the look on [Justin's] face and everyone else's face, and the feeling in the entire room."

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Timberlake blogged Sunday that he was "almost brought to tears" by a video montage of Pearl Harbor, World War II and the Sept. 11, 2001 attacks. "[It was] a surreal moment to be in that room with so many of our great Marines who have such a different type of connection to those stories," he wrote.

De Santis said was "completely honored" to watch the tribute with someone as "selfless" as Timberlake. 

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"It was a great time," she gushed about the evening. "He had a smile on his face the whole time."

Timberlake enjoyed himself as well, writing that De Santis "seemed to be so humble and honest… very cool."

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"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 added, referring to those who serve. "Last night changed my life and I will never forget it."