The Japanese schoolgirl trio – who combine metal and ‘idol pop’ – were manufactured to win over Japan’s geek hardcore. So how have they won over the metalhead faithful worldwide? The band reveal all

Here’s the thing about Babymetal: the entire concept is ridiculous. Three pint-sized teenage girls from Japan performing choreography in front of a band of middle-aged, heavy-metal session musicians and singing songs about their demands for chocolate. It’s silly, and by rights a true metal fan should hate it.

But as proven at July’s Sonisphere festival, they don’t. There were no bottles of piss hurled at Babymetal, a reception that has been lavished upon novelty rock-festival bookings from Daphne and Celeste to Kelly Osbourne. Instead a circle pit the size of Shinjuku opened, and that most genuine of metalhead welcomes – merry jocular violence – ensued.

In fact, they were so well received at Sonisphere and at a headline show at London’s Forum that they’re coming back for a victory lap, with enough support for them to play Brixton Academy. So why would anyone in Britain want to watch a sugar-coated, schoolgirl pop-metal group?

Key Kobayashi, better known as Kobametal, the group’s producer, pins their success on Babymetal’s alternative to the male, white norm: “Rock music hasn’t changed much over its history,” he says. “When a group from the other side of the world suddenly appears playing something so weird, it captures your attention.”

The video for their breakthrough song Gimme Chocolate!! has generated 17m YouTube views since it was published in February 2014. Clad in medieval corsets and frilly black and red miniskirts, 16-year-old Suzuka Nakamoto (Su-Metal) and 15-year-olds Moa Kikuchi (Moametal) and Yui Mizuno (Yuimetal) dance super-cute choreography in front of a giant statue of the Virgin Mary, backed by musicians in skeleton outfits, as a vast sea of fans throw their hands into a modified version of the devil horns based on the Fox God, the divine entity credited with selecting Babymetal to pursue a Bill & Ted-like quest to reunite the world with the power of metal. The video ends with the baffling invitation to “see you in the mosh’sh pit”.

As outrageous as their aesthetic may be, their self-titled 2014 album has been a serious contender in the metal world: it topped the metal charts on iTunes around the world, despite the band being signed only in Japan and their lyrics being in Japanese; the queue at their recent New York show wrapped halfway around the block of 34th Street and 9th Avenue; genre giants from Slayer to Metallica to Anthrax have fallen over themselves to take photos with the girls backstage at festivals.

“If Babymetal had been American, you can bet they would have been laughed right off the planet, but there is something truly unique about Japanese entertainment that it can get away with peddling something that’s a bit ludicrous and unthinkable,” says Stephen Daultrey, music editor at extreme-culture magazine Bizarre. “It’s fascination, really – we’re just too fascinated by Babymetal to even care whether they’re good or not, or that they were manufactured.”

Facebook Twitter Pinterest Babymetal at Sonisphere. Photograph: Dana (distortion) Yavin

The artificial nature of their formation is no secret, however. In fact, the three members had no interest in metal before joining the group, nor did they even know what it was. “I’ve never been in a moshpit,” admits Yuimetal.“I think I’d get smashed to bits.”

Instead, they came to the project as members of junior-high girl group Sakura Gakuin (of which Yuimetal and Moametal are still members) and had ambitions of becoming stars in Japan’s booming “idol pop” industry, composed of extremely youthful manufactured groups, who must appear saccharine, innocent and cute at all times. In an effort to get their groups noticed in this crowded field, talent agencies and labels are trying all sorts of weird fusions to capture a slice of the growing domestic market of loyal obsessive fans known as otaku – stay-at-home pop-culture nerds whose disposable income fuels the anime, manga and idol-music industries. The results, of which Babymetal are one, are sometimes as thrilling and experimental as they are absurd. Check out the sensory overload of Momoiro Clover Z, whose song Roudou Sanka was written by the Go! Team’s Ian Parton; and Dempagumi.inc, whose demented cover of Sabotage is equal parts Beastie Boys and Banana Splits.

Babymetal have progressed beyond the idol genre, though: “When we started out we only played at idol festivals, but now it’s like this weird mix where they react partly like an idol crowd and partly like a rock crowd,” says Su-Metal. “It’s chaos.”

The band now describe themselves as kawaii metal, kawaii meaning “cute” in Japanese. A recent show I saw at Makuhari Messe in Chiba, near Tokyo, drew 9,000 fans, most of whom were not otaku but regular rock kids, adhering to metal’s time-honoured dress code of black T-shirts and sweat. Once you get past the initial hilarity of a Babymetal show, the quality of the music begins to emerge: wildly supersonic guitar solos, doom-laden organs, industrial dual-pedal kickdrums, the lot. Lead singer Su-Metal may be pint-sized, but she’s a commanding presence on stage, her aloof vocal style well suited to their metal melodies.

Producer Kobametal fuses the heavy sound he has loved since childhood with the idol pop that is ruling the charts in Japan right now. It sounds cynical – it is cynical – but it’s also made with care. “Being schoolgirls means they can only work in the studio till 8pm, but the girls know they’d never get away with cutting corners,” Kobametal notes.

Facebook Twitter Pinterest Babymetal in London. Photograph: Dana (distortion) Yavin

Lyrically, if you don’t speak Japanese, you’re missing out. Yes, there are singalong English bits in Gimme Chocolate!!, but some of Babymetal’s Japanese lyrics are delightfully tongue-in-cheek. Onedari Daisakusen (which translates as Manipulation Strategy) offers practical advice to teens on how to extract extra pocket money from one’s father with a well-timed shoulder-massage/flattery combo, though you could also read it as a knowing insight into how idol groups titillate their core fanbase of otaku men with fat wallets and Lolita fetishes.

Being a teen group, they have some love songs, but more often the lyrics cut a little deeper. Megitsune (Vixen) is about the beguiling power women wield over men, while Ijime, Dame, Zettai (or Bullying, Unacceptable, Absolutely) pleads with the listener to not stand by while someone is being bullied.

“My friends tell me I’m like a different person [in Babymetal] than when I’m in class,” smiles Yuimetal. Moametal adds: “My friends were quite envious that we performed with Lady Gaga [with whom the band toured the US], but they’re also so supportive. They sing Babymetal songs whenever we go to karaoke.”

Citing the limitations of balancing school life with touring schedules as one reason, Kobametal says he doesn’t plan to go chasing overseas success. He says the girls might have a go at recording some songs in English, but if it sounds rubbish they’ll stick to what they do best and see where it leads them.

“We’ve reached fans around the world without localising anything, and the fact that Babymetal sound different from other metal bands is what people like about us,” he says. “So I’ve come to think that perhaps we should stay as we are.”