The Betch Is Back: Liam Sullivan

 Metro Center 

SPRING IS IN THE AIR, which means that it's shoe-shopping season! Though for Kelly, the Valley girl in Liam Sullivan's hilarious YouTube hit, "Shoes," every day is perfect for buying new kicks.

In the award-winning video, the awkward, headstrong Kelly argues with her disapproving parents and her indulged star-athlete twin brother, all portrayed by Sullivan.

Storming away from a birthday debacle, Kelly embarks on a shoe-shopping spree against a janky techno beat. The massively popular video transformed Sullivan from struggling stand-up to cyber-celebrity.

This weekend, Kelly appears in 3-D at the Warner Theatre as Sullivan opens for pal Margaret Cho's "Beautiful" tour.

He conceived Kelly in 2005 by playing around with his voice. "I just found myself saying, 'Shaat up! Betch!' That's how she started. ... I enjoy talking that way," Sullivan says.

Kelly stumbled a bit at first as Sullivan ironed out her wardrobe and milieu. "I first did her as a stand-up routine, but it didn't really work, because I didn't have the look of her going. It was just, 'Oh, that's just another Valley girl character,'" says the 34-year-old comedian.

The song "Shoes" popped into his head after listening to a girl talk about spending $300 for a pair. Suddenly, he envisioned Kelly as a recording artist or even a video diva. "So I dressed up as Kelly, went onstage and did the song, and it worked. It was one of those moments where it could really be hilarious or embarrassing. I didn't really know what I had. It's just grown into the huge following."

Kelly's follow-up songs, "Let Me Borrow That Top" and "Text Message Breakup," are equally popular. Despite, or perhaps because of, Kelly's aggressive materialism, physical oddities and mental vapidity, Sullivan sees her as a heroine.

"I didn't want to make her the butt of the jokes, because otherwise, it's just me making fun of girls."

» Warner Theater, 513 13th St. NW; Thu., 8 p.m.; Fri, 7 & 10 p.m., $28.50-$45.50; 202-783-4000. (Metro Center)

Photo courtesy Amy V. Cooper