What happened with Sakurazaka46 15th Single Formation Reveal?

On the late-night variety show 'Soko Magattara, Sakurazaka?' (TV Tokyo), Sakurazaka46 revealed the formation for their 15th single 'Lonesome rabbit.' Morita Hikaru holds center on both A-sides — a first in sakamichi group history — while Kojima Nagisa and Nakagawa Chihiro earned their first-ever selection spots.

What triggered the Sakurazaka46 15th Single Formation Reveal trend first?

May 17, 2026 (9:28 PM JST): Sakurazaka46 official X account previewed the night's broadcast, confirming a 'Lonesome rabbit' formation reveal

Why are people reacting to Sakurazaka46 15th Single Formation Reveal?

X activity spiked sharply between 1:17 and 1:40 AM JST on May 18, immediately after the TV broadcast ended. Three distinct reaction clusters emerged: celebration of Morita Hikaru's unprecedented dual-center achievement, emotional congratulations for Kojima Nagisa and Nakagawa Chihiro on their first selection spots, and broader praise for the BACKS members' performance quality.

Sakurazaka46 Drops 15th Single Lineup — A Sakamichi First

Entertainment Tokyo May 17, 16:10 UTC

Why now?

First sakamichi double A-side dual center

Sakurazaka46 15th Single Formation Reveal — Illustration: WhyTrend

On the night of May 17, 2026, Sakurazaka46's weekly TV Tokyo variety program 'Soko Magattara, Sakurazaka?' aired the second half of its 'Spring BACKS Festival' segment — and closed with a formation announcement that sent Japanese social media into a frenzy well past midnight. The headline moment: Morita Hikaru will center 'Lonesome rabbit,' the second song on the group's 15th double A-side single ('Lonesome rabbit / What's "KAZOKU"?')

She already holds center on the first A-side, 'What's "KAZOKU"?' — making her the first member in the entire sakamichi idol series (which includes Nogizaka46, Keyakizaka46, and Hinatazaka46) to center both songs on a double A-side release. Multiple Japanese entertainment outlets including ORICON and ModelPress confirmed this milestone.

Two third-generation members, Kojima Nagisa and Nakagawa Chihiro, received their first selection spots. Fans who have followed them since their debut roughly two and a half years ago flooded X with emotional congratulations. The reaction was immediate: posts peaked between 1:17 and 1:40 AM, minutes after the TV broadcast ended and the Lemino stream went live.

The episode also featured the 'BACKS Festival' variety challenge — members not in the main selection competed in a high-pressure word-chain game with giant balloons as a backdrop. The segment drew its own wave of praise, with fans noting that the non-selected members' skill level makes the selection/BACKS divide feel increasingly narrow.

What to watch next: The 15th single 'Lonesome rabbit / What's "KAZOKU"?' is the next major release milestone for Sakurazaka46. With a historic dual-center achievement locked in and two new faces joining the lineup, attention will now turn to the full single rollout, including music video releases and promotional activities.

Primary Japanese source

Key post from X

Shown in Japanese because it is the original source post behind the trend.

/／深夜1:20より配信開始📢 \＼ 🌸#そこ曲がったら櫻坂？【力を合わせて豪華ケータリングをゲット！春のBACKS祭り！後半】巨大風船を背にプレッシャーしりとり🎈 衝撃の結果をお見逃しなく👀 🌸｜ #櫻坂46 #レミノ

@Lemino_official ♡1,475 🔁272 View on X

Japan context

For readers outside Japan

The 'sakamichi' series is a family of major Japanese idol groups under Sony Music; a milestone within this system — like a member centering both songs on a double A-side single for the first time ever — carries weight across the entire fandom, not just Sakurazaka46 followers.

In Japanese idol groups, the 'formation' (who stands where on stage, and who is 'center') is announced separately from the single itself and is treated as a major event. The center position is the most prominent role and is closely watched as a signal of management's confidence in a member.

Sakurazaka46 is one of three active sakamichi groups; the others are Nogizaka46 and Hinatazaka46. A 'double A-side single' means two lead tracks are released simultaneously, each with its own music video and formation — making Morita Hikaru's dual-center status doubly significant.

The 'BACKS' members are those not selected for the main formation; they perform in separate concerts and are a major part of Sakurazaka46's identity and fan culture.
Japanese entertainment news outlets ORICON and ModelPress, both cited in the sources, are considered authoritative for idol industry news in Japan.

Reader brief

What happened: On the late-night variety show 'Soko Magattara, Sakurazaka?' (TV Tokyo), Sakurazaka46 revealed the formation for their 15th single 'Lonesome rabbit.' Morita Hikaru holds center on both A-sides — a first in sakamichi group history — while Kojima Nagisa and Nakagawa Chihiro earned their first-ever selection spots.
Why it is trending now: First sakamichi double A-side dual center
First signal: May 17, 2026 (9:28 PM JST): Sakurazaka46 official X account previewed the night's broadcast, confirming a 'Lonesome rabbit' formation reveal
Why people reacted: X activity spiked sharply between 1:17 and 1:40 AM JST on May 18, immediately after the TV broadcast ended.
What to watch next: The 15th single 'Lonesome rabbit / What's "KAZOKU"?' is the next major release milestone for Sakurazaka46.

Quick 5W1H Who Sakurazaka46 / Morita Hikaru 
 What 15th single formation announced 
 When May 17, 2026 (late night broadcast) 
 Where TV Tokyo / Lemino streaming 
 Why First sakamichi double A-side dual center 
 How Live reveal on variety show 
 Source check 4 sources 2 official  oricon.co.jpmdpr.jptv-tokyo.co.jpsakurazaka46.com  

Timeline

May 17, 2026 (9:28 PM JST) Sakurazaka46 official X account previewed the night's broadcast, confirming a 'Lonesome rabbit' formation reveal
May 17, 2026 (late night, ~12:50 AM JST) TV Tokyo broadcast of 'Soko Magattara, Sakurazaka?' aired the BACKS Festival segment and the 15th single formation announcement
May 18, 2026 (1:20 AM JST) Lemino streaming of the episode began; X posts peaked as viewers reacted to the formation reveal
May 18, 2026 (1:46 AM JST) ORICON published a breaking news article confirming Morita Hikaru's historic dual-center status

Reactions

Fans celebrate a historic milestone and two long-awaited debut selections

Morita Hikaru dual-center celebration 35%

Fans highlighted the 'sakamichi first' angle, congratulating Morita on cementing her status as the group's ace.

First-selection congratulations 40%

The largest cluster: fans of Kojima Nagisa and Nakagawa Chihiro posted highly emotional congratulations, many noting they had waited years for this moment since the third-generation members joined.

BACKS member praise 25%

Viewers of the BACKS Festival segment praised the non-selected members' skill, with several posts expressing that the selection/BACKS divide feels increasingly meaningless given the group's overall talent level.

Original Japanese signals

Primary posts are shown in Japanese because they are the source evidence; the English summaries above explain what they mean.

40%

Morita Hikaru dual-center celebration

Fans highlighted the 'sakamichi first' angle, congratulating Morita on cementing her status as the group's ace.

↗ Primary source YouTubeで見る

Original post
本日5月17日(日)24:50～テレビ東京「そこ曲がったら、櫻坂？」は「力を合わせて豪華ケータリングをゲット！春のBACKS祭り！後半」です🍱❤️‍🔥 「Lonesome rabbit」のフォーメーション発表もございます！ぜひご覧ください🌸 #そこ曲がったら櫻坂 #そこさく #櫻坂46

櫻坂46 @sakurazaka46 ♡ 4,599 🔁 647 View on X

35%

First-selection congratulations

The largest cluster: fans of Kojima Nagisa and Nakagawa Chihiro posted highly emotional congratulations, many noting they had waited years for this moment since the third-generation members joined.