Strawberry Prince (StPri) Releases New Music Video 'IyaIya Seijin' in Collaboration with Nayutan Starman, Following Hit 'SukiSuki Seijin'

STPR Co., Ltd. (Headquarters: Shibuya-ku, Tokyo; Representative: Masato Kashiwabara; hereinafter "STPR") announces that its 2.5D idol group "Strawberry Prince (StPri)" has released the music video for their new song "IyaIya Seijin."

This track is an original composition by Vocaloid producer Nayutan Starman, known for producing "SukiSuki Seijin," one of StPri's representative songs with over 40 million YouTube views. Alongside the music video release, STPR is launching a TikTok campaign and a digital campaign.

On June 4, 2026, marking their 10th anniversary since formation, StPri has released the music video for "IyaIya Seijin."

Lyrics, composition, and arrangement were handled by Nayutan Starman, who has produced numerous hit songs including "SukiSuki Seijin." The song expresses an awkward yet sincere feeling of "I don't like it unless it's you!" through a pop and highly addictive sound. It features a charming and playful worldview, with catchy phrases that stick in your mind after just one listen.

The music video also highlights choreography by SACO MAKITA. The dance, synchronized with the memorable phrase "I don't like it unless it's you!" enhances the song's cuteness and pop aesthetic.

Alongside the music video release, STPR is launching a TikTok campaign and a digital campaign. On TikTok, fans are invited to create and post videos using the official audio of "IyaIya Seijin." This listener-participation project encourages users to express the world of "IyaIya Seijin" through dance, lip-sync, or everyday scenes.

As a new "Seijin Song" from StPri celebrating their 10th anniversary, enjoy the music video and join the celebration.

[MV] "IyaIya Seijin" / Strawberry Prince

YouTube: https://youtu.be/PoIgXeRTEyI?si=C1n4BWskkS_xRopd

Lyric, Music, Arrangement: Nayutan Starman

Recording Director: Yuichi Nitta (Gold Beats Factory)

Mix Engineer: Tomofumi Hosoi

Sound Direction: Gold Beats Factory

Illust: nanao

Animation: Ozusawa (studio Lit.)

Movie: EL-Y

Choreographer: SACO MAKITA

<Scene stills>

TikTok Submission Campaign to Commemorate the Release of "IyaIya Seijin"

To celebrate the release of the "IyaIya Seijin" music video, a TikTok submission campaign is being held. Participants who post a video on TikTok using the official audio of "IyaIya Seijin" with the hashtag "#IyaIyaSeijin" will be entered into a lottery to win one of 15 acrylic panels signed by their favorite member.

★ Selected participants may receive comments from StPri members on their videos.

[Application Period] June 14 (Sun), 2026 – July 12 (Sun), 23:59

[How to Participate]

① Select the official audio of "IyaIya Seijin" on TikTok

② Post a video with the hashtag "#IyaIyaSeijin"

③ Entry complete

[Prize]

Acrylic panel with autograph from a member of your choice (15 winners selected by lottery)

Campaign details: https://strawberryprince-10th-anniversary.stpr.com/news/news-0614-2/

Digital Campaign to Commemorate the Release of "IyaIya Seijin"

1. Song Sharing Campaign

Share the song on designated music streaming services and all participants will receive a limited-edition wallpaper image.

2. Library Addition Campaign

Play the song on designated music streaming services, add it to your favorites or library, and all participants will receive a limited-edition wallpaper image.

[Application Period] June 14 (Sun), 2026 – June 20 (Sat), 23:59

[Prize] Limited-edition wallpaper image

Campaign details: https://strawberryprince-10th-anniversary.stpr.com/news/news-0614-1/

Strawberry Prince (StPri) Profile

A 2.5D idol group active across various platforms, primarily video-sharing sites.

Formed in 2016 around leader "Nanamori." as a collective of creators who posted singing covers, gameplay streams, and more, launching "Strawberry Prince / StPri."

Their official YouTube channel has accumulated over 10.4 billion total video views, with over 4.4 million subscribers. Including individual members, their total social media follower count reaches 50.5 million (as of June 2026).

Their nationwide arena tour from January 2023 across 11 locations and 44 performances drew approximately 350,000 attendees. They also appeared on the 74th NHK Kōhaku Uta Gassen at year-end. In 2024, they hosted their own prime-time TV show on TBS. Their first single "Hajimari no Monogatari," released in June 2024, topped both the Oricon Combined Chart (June 17) and the Billboard JAPAN Top Singles Sales (June 12). Their first animated film, "Strawberry Prince the Movie: Hajimari no Monogatari ~Strawberry School Festival!!!~," released nationwide in July 2024, gained significant attention domestically and internationally, with overseas screenings beginning in June 2025. Their best album "Strawberry Prince Forever," released in January 2025, achieved a triple crown by topping the Oricon Weekly and Combined Charts (January 14, 20) and the Billboard JAPAN Top Albums Sales (January 12). The two-day "Stroberry Memory Vol. Forever!! 'StPri Best Album Release Party 2025'" held that same month attracted around 50,000 attendees. In June 2026, they celebrate their 10th anniversary, with a commemorative arena tour planned across 4 cities and 13 performances.

They continue to expand their activities to deliver joy to listeners.

Official Links

Official Website: https://strawberryprince.stpr.com/

Official YouTube: https://www.youtube.com/@StrawberryPrince

Official X: https://twitter.com/StPri_info

Official TikTok: https://www.tiktok.com/@stprinfo

Official Instagram: https://www.instagram.com/strawberryprince.info/

Official LINE: https://page.line.me/600lwgdb

About STPR Co., Ltd.