Kat Dennings: I'm So In Love with Kim Kardashian's Butt

Kat Dennings is a big fan of Keeping Up with the Kardashians, but even her mouth dropped when she saw Kim Kardashian's butt in person.

Kardashian -- who turns 34 today -- will appear on an episode of Dennings' CBS comedy 2 Broke Girls, and the actress admitted on Tuesday's The Elllen DeGeneres Show, "I was just so in love with her ass! I just spit talking about it, that's how passionate I feel!"

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But does the bootylicious reality star know how Dennings feels about her assets? Not exactly. "We would say a nice thing or two," she recalled. "Then [Kim would] turn around and Beth [Behrs] and I would be like (mouths the words), 'OH MY GOD!'"

She added, "It's beautiful! She's gorgeous. It's just, amazing!"

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Still not over it, Dennings proclaimed, "I've never seen an ass like that in my life."

Kardashian will appear on 2 Broke Girls' season 4 premiere Monday, October 27, on CBS.

The 28-year-old actress might have missed her chance with Mrs. Kanye West, but she has found romance with opera singer Josh Groban. Dennings also reveals to Ellen that she met the 33-year-old musician through her co-star Behrs.

“Yeah, she’s always talked about how great he is. They've been friends for years. And uh she thought we were both ya know nerds. So there, she was right," she revealed before blushing.

Groban also gushed to ET about his new gal. Check him out, below.