Before 4s4ki’s strode onstage, she demanded that the house lights be shut off, and then a pentagram graced the back screen as she performed under a red metal torii gate which seemed to be made of perforated metal.

As a warbling background of video depicted twisted urban scenes, and “mentally ill” flashing sequences of imagery across the back screen, 4s4ki alternatively presented herself like the dancer for Sia’s earliest videos, or a veteran heavy metal vocalist.

The music displayed elements of hiphop and glitch, but was probably leaning towards “Yami Kawaii”; a newish Japanese fashion of mixing cuteness with mental illness; Being that 4s4ki’s latest album is called “Castle in Madness,” this is, of course, fitting.

Her musical performance combined with the video and lighting visuals gave a disconcerting effect. It would be a purely alien experience to most people in this world. However, the overall effect remains an engaging one; like one is drawn to find out more about what is going on, regardless of how weird it may seem; as if seeing an alien craft crash nearby, and feeling unable to do otherwise but to go over and investigate.

As she performed under overwhelming white lighting, it was sometimes hard to make out precise details of her figure, but one COULD see the outline of her playing guitar aggressively on the third song. She then continued to do so, as a DJ – like a black outline behind her – triggered her backing tracks.

Fifteen minutes into her set, 4s4ki’s started a slower song with a background of blue water imagery dancing behind her red torii gate. And, as she sang about the Moon, it started to rise on the screen, taking the place of the water. As the song came to an end, and the audience applauded, she handed her guitar to a roadie and thanked the thousands of fans in attendance for coming to see her despite all difficulties.

With one lone white spotlight beaming down from above her red torii gate onto her pink-haired head, she pulled up to a keyboard at waist height and played a plaintive piano ballad all by herself. Midway through, the pace started picking up, and her vocals started speeding up as if in a rant against an uncomprehending lover. “Kimi, DOUSHITE,” (WHY do you,) she sang, as if crying to a lover. And, then she sang, “Tadaima” (I’m home) as the last piano chords died out. After about ten seconds of silence, where the audience seemed to wonder what to do, the crowd started applauding enthusiastically.

4s4ki then started yet another song alone, with a keyboard patch that sounded like bells, and a vocal line that sounded like another insane rant against a lover. Then she went silent and reappeared seconds later on center stage singing with white beams of light streaming behind her. As the track picked up in a hip-hop beat resembling industrial drills, a trio of X’s lit up the stage with white light, and 4s4ki sang at the audience like the combination of a woman coming undone, and the Queen of her own empire. As she ran off to stage left in the second of silence for the prechorus, she leapt into the air and the bright light caught her pink hair as if in an action movie sequence before she ended the song and the audience applauded wildly again.

For the following number, as with the first few songs, disconcerting imagery scrolled across the back screen in orchestrated madness, as the track drove on like a dirty glitchy drum n bass track. For the breakdown, four beams of white light framed her figure on center stage as she seemed to sing in triumph while images of old-school computers whose screens bore her image rotated on the video screen behind her.

Without taking a break between songs, the next track started up in the closest version to a Beyoncé number that a Japanese person could muster, but the glitch starting to crawl back in, the bass got incredibly dirty, and 4s4ki delivered her vocal cues while running about the stage and gesticulating at the audience as if to say, “Yeah, maybe I’m nuts, but, do you know what? This is MY world!” And, indeed, for whatever demons might be troubling this young woman, on this stage tonight – and on these recordings – she IS triumphing.

With twelve minutes left in her stage time, 4s4ki played a song with odd syncopated kick drum hits like mattresses hitting an apartment floor, and a meandering vocal line akin to a traditional asian folk song trying to be remembered by a small child high on sugar.

Quickly shifting into the next song, 4s4ki squealed “The next song is the before-last one! Thank you, eh!” and she was already off and running around the stage as if there were some manner of emergency. As the song hit a musical breakdown, 4s4ki manned center stage and got the audience of thousands clapping over their heads to the beat, before the track morphed momentarily into something resembling a Pet Shop Boys hit, but which once again shifted into a vintage computer’s nightmare music. Before the end of the track, it shifted again to hard trance during which 4s4ki delivered vocals like vocaloid samples. The number eventually ended on a sample akin to a twisted old-school video game sample while 4s4ki’s vocals resembled a furiously delivered monologue heard through a broken telephone. The word “obon” scrolled across the back screen in various neon colours, indicating that this song was about the Japanese festival to honor one’s late relatives; which takes place every August. All in all, 4s4ki is probably the artist Kyary Pamyu Pamyu’s management wishes she had been.

As the song finally ended on a twisted version of a vintage video game’s theme, 4s4ki gently said, “this next song is the last one for real! Thank you so very much for coming out! Please enjoy Fuji Rock until the very end.” And, the last song proved to be the most normal offering of the bunch; a two minute glitchy drum’n’bass number with nothing terribly eccentric about it. After the last note faded, 4s4ki cried out, “Thank you very much, I am 4s4ki!”. Then the audience applauded and left the venue.