On June 5 (Thu) and 6 (Fri), 2025, Japanese music production company WACK held its sixth overseas concert series, WACK in the UK vol.6, at The Underworld in London.

Previous installments took place on November 16, 2023; March 27, August 28, and November 26, 2024; and March 26, 2025, all at The Underworld. Vol.1 featured ExWHYZ, ASP, and a special unit called AiNATOAOI, composed of AiNA THE END and dancer/model Aoi Yamada. Vol.2 brought GANG PARADE, ASP, and KiSS KiSS. Vol.3 saw ASP, BiS, and MAMESHiBA NO TAiGUN TONAIBOUSHO a.k.a. MONSTERIDOL, while Vol.4 featured ASP, ExWHYZ, and MAMESHiBA NO TAiGUN. Vol.5 once again included ASP, alongside GANG PARADE and KiSS KiSS.

Now in its sixth edition, WACK in the UK was held for the first time across two consecutive days. Here is a report from Day 2 of the event.

WACK in the UK vol.6 — Day 2 On-Site Report

With the support of Tom Smith from JPU Records, WACK managed every detail of this DIY live concert—from booking the venue to coordinating the event locally. Since its inception, the series has consistently drawn over 300 attendees, with fans from the UK and other countries outnumbering Japanese visitors.

Junnosuke Watanabe, WACK’s former CEO, stepped down to pursue graduate studies in the UK and currently resides there. On January 6, 2025, he launched DiG YOUR OWN IDOLS, an English-language media platform that spotlights not only WACK groups but the broader Japanese idol culture as well.

This sixth edition was the first 2-day installment, and Day 2 welcomed three groups performing in London for the very first time. These were PIGGS, a six-member idol group produced and led by Pour Lui; MAPA, a six-member group formed around Coshoji Megumi; and ZOCX, a six-member group produced and fronted by OOMORI SEIKO, performing in a special lineup with KAREN AIZOME.

Just before the 7:30 p.m. start, Watanabe took the stage to re-announce the evening’s performers, drawing loud cheers from the audience. He gave a quick overview of the rules in English and encouraged everyone to enjoy the night, saying, “It’s the first time for all three groups to perform in London—have fun!”

MAPA

A gentle piano melody played as the opening SE, and the crowd clapped along as Coshoji Megumi, Ushiro Mayo, Shio Yusura, Jinzai Emu, Touka Kurumi, and Midoriyama Misaki stepped onto the stage. They opened the show with “Calling box,” a song highlighted by beautiful unison vocals. One of MAPA’s distinctive features is Coshoji’s spoken-word poetry embedded mid-song—an element rare among idol groups. Often described as “theatrical,” their performances are filled with storylines. This continued with the post-rock-style guitar-driven “Ame no Shiro (Rain Castle),” enveloping the venue in the MAPA universe.

After brief introductions, they asked the crowd in English, “Are you ready to have fun?” Then came the cute and whimsical “Kirin♡Time,” starting with the lines, “I like giraffes… but I like you even more,” followed by “Don’t compare me to anyone!”—spoken by Jinzai and Ushiro, respectively. This song showcased the group’s wide stylistic range. Coshoji then recited, “Father’s father? Father’s mother? Mother’s father? Mother’s mother? That’s all,” leading into the quirky and original “Shitenno (The Four Elders),” where the chorus repeated “Grandpa! Grandma! Great-grandpa! Great-grandma!”—overflowing with humor and joy.

They continued with “SUMMER SHOOTER” and “Kaiju GIGA,” keeping the audience engaged. Then came a dramatic shift: over a delicate piano line, Coshoji delivered a heartfelt spoken intro to “The Day I Quit Being an Idol.” As the song progressed, the sound swelled and intertwined with the members’ vocals, building emotional intensity. Even though the lyrics were in Japanese, the international audience listened intently. To close their set, they performed the melodic “Zettai Unmei Gokko” with full force, exiting the stage to enthusiastic applause.

PIGGS

As pig squeals played through the speakers and the upbeat opening SE of PIGGS kicked in, the audience responded with chants of “Oi! Oi!” Pour Lui, SHELLME, BAN-BAN, KINCHAN, BIBI, and SU-RING burst onto the stage to loud cheers, launching straight into the punk-influenced “Fleeting.” The aggressive opening sent the audience jumping and raising their hands in response to the group’s raw energy.

Next came “NAKED BORN NAKED DIE,” during which the members linked arms and swayed side to side. The crowd matched their energy, and as the song progressed, the temperature in the venue noticeably rose. Without pause, they charged into “LINK EMOTION,” with high-octane vocals and choreography that made it easy for fans to join in. The unity between stage and floor was electric.

“Hello, London! We’re PIGGS! Nice to meet you!” they shouted in English, then introduced themselves one by one. BAN-BAN showed off her biceps, while KINCHAN performed her signature “Omochi Punch,” blending Japanese idol humor with English phrases to entertain the London crowd.

“Do you like party?” SHELLME asked. “Next song is dangerous, because it’s very, very, very exciting. Daredemo dekiru! Let’s dancing!” The group dove into the catchy and soulful dance track “Dejavu.” They kept the momentum going with the melodic “Ikite Kaeru,” the emotionally charged rock tune “1 Millimeter Demo,” and crowd-favorites “Toraeru” and “PIGGS – Mona Lisa.” With each song, the energy in the room climbed higher, and by the time they finished, the heat and humidity had reached a boiling point—ending their set in a sweaty, euphoric high.

ZOCX

To a fusion of traditional Japanese sounds and digital beats, OOMORI SEIKO, CHAO AIMI, SENRITSU KANANO, SENTSUBAKI MAYU, AMAKUNI MIYUKI, and NEKONEKONEKO HAU took the stage, joined by special guest AIZOME KAREN for this one-night-only lineup (KANANO SENRITSU did not participate in this performance). With heavy guitar riffs and chants of “Oi! Oi!” from the crowd, they kicked off the set with “ZOC Jikken-shitsu (ZOC Laboratory).” OOMORI’s piercing screams drew the audience in immediately. Their powerful yet artistic vocals intertwined in the chorus, where the repeated shout of “ZOC! ZOC!” left a strong impression.

“We brought Japanese underground culture to London. Are you ready?” OOMORI asked in English, then launched into the anthemic “AGE OF ZOC.”

During the MC, the members briefly introduced themselves in Japanese. Announcing the next track as “a very, very sexy song,” they moved into the soulful “LiBiDo FUSION,” performed with alluring choreography. The next track, “GIRL’S GIRL,” began with the provocative line, “If life isn’t cute, is it even worth living?” and featured multiple musical shifts within one song, showcasing their dramatic range.

“14sai” followed, a haunting song that began with OOMORI’s solo vocals. The track’s theatrical development and intense stage movement left the crowd spellbound. “FLY IN THE DEEPRIVER” thundered through the venue with its repeated scream of “Kuso! Kuso! Kuso! Kuso!” (Damn! Damn! Damn! Damn!), creating an explosive atmosphere.

They continued with “CUTTING EDGE,” a melodic yet punk and chaotic anthem that represents the essence of ZOCX. Then came “family name,” one of ZOC’s signature songs. Before launching into it, OOMORI declared in English, “You decide your sex, gender, age, and your life.” With that, they closed their set by radiating unfiltered artistic energy.

A Special Surprise: Pour Lui, Coshoji Megumi, and OOMORI SEIKO Reunite for “primal.”

Junnosuke Watanabe returned to the stage, asking the crowd in English, “Are you having fun?” Cheers erupted. “Do you know first BiS?” he asked—and the crowd roared even louder.

“I was the manager of first BiS,” Watanabe revealed, then called Pour Lui, Coshoji Megumi, and OOMORI SEIKO to the stage. Without much explanation, he simply said, “Enjoy,” and exited.

Then, Pour Lui announced the song title:

“primal.”

A moment of stunned silence was quickly replaced by thunderous applause and shouts of joy.

“primal.” is a legendary song from the early BiS days. With emotional guitar riffs and choreography that features the performers raising their arms and turning away from the audience during the chorus, the song has had a deep influence on Japanese idol culture. In fact, OOMORI SEIKO once performed this song alongside the original BiS at the underground venue Shinjuku LOFT in Japan.

Now, the anthem that symbolizes Junnosuke Watanabe and WACK echoed across London.

Despite being released in 2011 and despite the performance happening in a foreign land, the power of music transcended borders. As the chorus played, fans began mimicking the signature choreography—raising their arms and turning around. The movement spread like a ripple across the venue, reminiscent of the impact BiS had on the Japanese scene.

The song’s four minutes flew by. At the end, Pour Lui, Coshoji, and OOMORI all looked satisfied and visibly moved, their expressions glowing with joy.

Watanabe reappeared and declared, “How wonderful primal. is!” in praise of the performance.

When asked for comments, OOMORI expressed her gratitude in English: “We brought underground culture and live music. Thank you.” Pour Lui said, “Music goes beyond borders! My heart is hot!” while Coshoji, moved to tears, added, “I love you all so much! I’m really happy. Thank you for waiting for us!”

Finally, all the performers reassembled on stage. Watanabe introduced AMAKUNI MIYUKI as a former WACK member. SHELLME, with the energy of a true “Japanese gyaru,” gave a final shoutout: “Life is enjoy! When you’re sad, remember this day—PIGGS, MAPA, ZOCX, and Watanabe-san. We are family!”

Special guest KAREN AIZOME also shared her thanks in English.

Everyone posed for a group photo. As the crowd cheered one last time, Watanabe closed out the event with: “Thank you! See you again!”