Credit: Michael Rozman/Warner Bros.

Ahh, young love!

Alex Pettyfer did his best to remain tight-lipped about his relationship with Dianna Agron during a Friday appearance on The Ellen DeGeneres Show, but that didn't stop the talk show host from getting a few sweet details about the I Am Number Four costars.

"She's an amazing woman and she's got this old school, classic movie star elegance to her," Pettyfer gushed of the Glee star, 24. "She's amazing."

"You like her a lot?" DeGeneres, 53, asked.

"Yes, she's a very nice girl," the actor responded before taking a sip from his coffee cup.

"Oh, here comes the water," DeGeneres teased as Pettyfer took another sip. "And that is a big tell that you are."

With a sly grin, the 20-year-old Brit told DeGeneres, "I'm just very happy in my personal life."

Agron, however, was more forthcoming in a recent interview with Sugar magazine, saying that Pettyfer "might see himself as a bad boy, but he's actually very sweet in real life."

"I think it's important to have your differences in any relationship," she said. "I wouldn't want to be dating a carbon copy of myself. That would just be boring."