Rebecca Flint, 14 – aka Beckii Cruel – is an internet hit among anime fans and her debut album is tipped to top Japanese charts

Like most 14-year-old girls, Rebecca Flint likes to dress up and dance. But unlike most girls, she records and posts her performances on YouTube.

The results have made her an ­internet phenomenon in Japan, home of the anime cartoon characters she imitates. More than eight million people have watched Rebecca performing as Beckii Cruel, dancing to bouncy J-pop (Japanese pop music) and anime theme songs in the attic of her home on the Isle of Man.

Her success has led publishing giant Tokuma Japan to sign up Beckii, teaming her with 18-year-old French college student "Sara Cruel", from Lyon, and a 16-year-old student from Portsmouth known as "Gemma Cruel". The trio – Beckii Cruel and the Cruel Angels – release their debut album in Japan on Wednesday, when it is expected to reach the top of the charts.

Beckii's looks have created a sensation in Japan, where she has become a "moe idol", a female worshipped for her small face, large eyes and slender limbs, similar to those found in anime characters – the Japanese animation-style heavily influenced by manga comic books.

Anime has a huge following in Japan across all sections of society. Taro Aso, a former prime minister, is a self-confessed anime obsessive, reading up to 20 comic books a week.

"The perceived virtual existence and borderless nature surrounding Beckii are a catalyst for stirring fantasies," said Toshiyuki Inoue, an IT journalist, summing up the popularity of moe artists.

Kaori Sakurai, a freelance writer, said that the otaku – anime geeks who worship teenagers like Beckii – will often avoid pretty girls in real life, fearing that they would simply dismiss them. But they have been won over by Beckii, who appears as just another fan like them.

Beckii's popularity in Japan rocketed after her YouTube videos were picked up by popular Japanese website Niko Niko Douga. Her Japanese DVD debut, This is Beckii Cruel: Too Cute to be Real, was released last November and debuted at number eight in Japan's DVD charts. Beckii, who already features in Japanese TV commercials for chewing gum, performed live for the first time at Akihabara, home of otaku culture in Tokyo, last October.

The daughter of a policeman and a former dance instructor, Beckii first became interested in Japanese cartoons and comics three years ago when she picked up a translated copy of Fruits Basket, a Japanese girls' manga created by Natsuki Takaya. Since then, she has been voraciously reading manga and watching anime, while also studying Japanese.

Beckii's idea to film herself in "cosplay" – derived from costume play – followed and an internet star was born. Hundreds of thousands of Japanese teenagers indulge in "cosplay", with conventions regularly held around the country. Tokyo Dome, home of the Yomiuri Giants baseball team, is a regular weekend hangout for teenagers dressed as their favourite anime or manga characters.

At a recent press conference in Japan alongside her father, Derek, Beckii said she was aware that her age and the nature of her videos would attract some unwanted attention. "I'm well aware of the dangers of the internet; my school back home on the Isle of Man is good at educating us on that," she said.

Beckii has had her own webpage since she was four – her older brother, Ryan had his at six. Ten years on from setting it up with her father, who says he has educated his daughter on the dangers of the internet, she now has the second most subscribed website among Japanese musicians. The expectation surrounding the release of her album this week suggests her incredible rise to fame shows no signs of slowing down.