Hatsune Miku will appear in concert at the Nokia Theatre

It’s strangely fitting that the biggest guest at the 20th annual Anime Expo at the Los Angeles Convention Center this weekend won’t physically be present. Japan’s virtual pop star Hatsune Miku — the petite “android diva” created by Crypton Future Media in 2007 through a combination of holography, computer animation and computer-generated vocals — will appear in concert at the Nokia Theatre on Saturday in her first “live” performance in the U.S.

Digitally animated singer Hatsune Miku Real musicians, including J-pop band Nirgilis, trio Kalafina and actor-singer Vic Mignogna, are also slated to perform as part of the Anime Expo festivities, which run Friday through Monday. But Miku, with her turquoise, ankle-length ponytails, impossibly slim figure and large eyes, perfectly embodies the fantastic creations the convention celebrates: beloved characters who exist only as images on film, computer data or drawings on a printed page.

Functioning much in the same way that San Diego’s Comic-Con International does for comic book enthusiasts, Anime Expo, the largest gathering of its kind in North America, offers fans of the vibrantly styled art form the chance to shop for videos, books, toys, T-shirts and other merchandise, attend panels and show off elaborately styled costumes at a special masquerade ball.

“The masquerade is always one of our premiere events,” said Marc Perez, chairman and chief executive of the Society for the Promotion of Japanese Animation, the nonprofit that manages the expo. “The amount of time people spend on a single costume is often astronomical. And when four or five individuals form a troupe to present a skit, it can easily involve several thousand hours: a very significant investment of time and passion.”

Attendees also will have the opportunity to see several features for the first time. “Last Exile: Fam, the Silver Wing,” a film based on the fantasy-adventure series “Last Exile,” will have its premiere at the Expo, and three other features will receive their U.S. openings: Hirotsugu Kawasaki’s “Onigamiden” depicts a war between oni (demons) and humans in medieval Kyoto, while “The Disappearance of Haruhi Suzumiya” comes as the follow-up to the offbeat series “The Melancholy of Haruhi Suzumiya,” about a high school girl who wields enormous power over the space-time continuum; “Mobile Suit Gundam 00 the Movie: Awakening of the Trailblazer,” is the latest installment in the long-running giant robot franchise.

Suzanne Beavdoin, left, and Jennifer Dupray pose as Sailor Moon and Sailor Chibi Moon at the 2010 Anime Expo Masquerade. (Stefano Paltera/For the Los Angeles Times)

Other Expo highlights include a music video competition and a trivia contest, classes in Japanese and a charity auction to benefit the Japanese Red Cross in its work for victims of the earthquake and tsunami.

There are also plans for topical panels examining issues such as piracy. Although anime and manga enjoy a growing audience in America, especially among tweens, teens and twentysomethings, piracy has become a serious problem, cutting into sales of titles on disc and in print.

“The fan base for anime continues to grow; Anime Expo and other conventions continue to grow. But I think anime and manga are struggling the way music did in the ’90s,” Perez said. “Individuals have a great appreciation for the content, but it’s often easier to acquire that content illegally than legally.”