At the I Love Anisong concert during the Anime Festival Asia Singapore, Godwin Choo and his friends will be enjoying the show performed by anime voice actors and singers by bursting into a synchronised dance of their own.

Their choreographed routine involves vigorous arm movements with light =sticks, interspersed with cheers such as "Hai!".

What they are doing is "wotagei", which is often practised at concerts and anime-related events.

"Wota" means "diehard fan of idols" and "gei" means art. So their energetic dance is a show of support for their idol so extreme that it has evolved into its own artistic subgenre.

Mr Choo, 20, who graduated with a diploma in law and management from Temasek Polytechnic earlier this year, is part of Singapore's few wotagei groups.

His two-year-old team is called Tengoku Parade, which started with nine fellow members from the polytechnic's Japanese Cultural Group.

It has grown to more than 20 members and is now open to anyone interested in wotagei.

On why wotagei is important, he says: "The idols are putting effort into their performance. We feel an obligation to show our appreciation.

"Doing wotagei also hypes up the concert mood."

A long-time fan of Japanese pop culture, he enjoys watching anime such as Highschool DxD and loves the J-pop girl group FES*TIVE.

He first saw wotagei at the 2013 edition of Anime Festival Asia Singapore.

At a screening of an anime voice actors' concert, he was intrigued by the action offstage: lightstick-wielding fans waving their hands in time to an anime theme song. Their actions were perfectly synchronised.

"It was a magical moment," he says.

After researching online wotagei videos uploaded by Japanese fans, he decided to form his own group.

The members meet once a week at the polytechnic's rooftop or youth hangout *Scape to practise their moves.

The routine is a combination of self-choreographed moves and actions learnt from YouTube videos.

They also record their own routines and upload the videos onto their YouTube Channel.

Another founding member is Ruzaini Ismail, 21, who is still a student at Temasek Polytechnic.

Mr Ruzaini, who goes by the stage name Ruru, travelled to Bangkok earlier this year to watch his favourite J-pop group FES*TIVE perform.

He also took time to collaborate with Thai wotagei practitioners and uploaded the video onto his YouTube channel.

To him, the beauty and challenge of wotagei lies in the entire group being in sync.

He says: "After constant practice, there will come a point where the moves become one with your body.

"The secret to mastering it is to simply feel the moves and feel the music."