Mesmerizer (song)

"Mesmerizer" (メズマライザー) is a 2024 song by Japanese music producer 32ki (pronounced "Satsuki") featuring vocals by Vocaloid virtual singer Hatsune Miku and Kasane Teto. The song's accompanying animated music video, created by Japanese animator "channel", reached 10 million views on YouTube within two weeks of its release, unprecedented for Vocaloid songs.

Background and release
The music video for "Mesmerizer" was released on April 27, 2024, and the song was released for streaming on May 17. The song was included on 32ki's first album, Circus's Detail, which was released during Niconico Chokaigi 2024. The song's stems have been made available to the public as part of the "Remix Project" by Dwango.

The song explores the theme of "mesmerism". The lyrics also examine the desire to escape from reality and the danger of losing oneself to escapism.

Music video
The music video for the song was created by "channel", whose fan-made animation for "Rabbit Hole" by DECO*27 went viral on social media in February 2024. In the music video, Hatsune Miku and Kasane Teto dance to cheerful singing and rhythmic effects, wearing clothing in the style of an American diner. Despite the video's bright colors and the song's upbeat instrumental, disturbing details are littered throughout the video. Teto's use of distress signals is hidden throughout the video, including her signing "help" in American Sign Language, showing the Signal for Help, and blinking the SOS pattern. Before the first chorus, the pose both Teto and Miku make with their hands and arms, combined with the tridecagram flashing "mesmerizer!!" in between them, makes the letters "SOS". This is the same pose used in the thumbnail.

Halfway through the video, Miku succumbs to hypnosis, and she begins to lose control of herself. During the "QUIZ TIME!" segment before Miku gets hypnotized, the first letters of each answer spell out "HELP", as well as the fourth letters spelling out "SOS". At the start of the final chorus, Miku goes completely insane and begins to dance wildly, contorting her body, and the subtitles become mojibake. Teto continues to dance, although visibly frightened by Miku's condition. During the final seconds of the video, although obscured by a shower of confetti, it is possible to see Teto's eyes close momentarily, her distressed expression fading to a vacant smile, implying that she also loses her sanity.

The music video for "Mesmerizer" uploaded to YouTube reached 10 million views on May 11, 2024, 13 days later. The song is also the third and fastest song to surpass one million views on Niconico utilizing Synthesizer V, and the second fastest among all Vocaloid songs. On June 27, 2024, the video surpassed 50 million views. A commemorative illustration was made by channel the following day.

Chart performance
The song debuted at No. 8 on the Billboard Japan Niconico VOCALOID SONGS TOP20 chart for the week, later topping the chart for five consecutive weeks, and entering the top 20 of "Japan Songs (South Korea)" for three consecutive weeks. It also debuted at No. 65 on the Japan Hot 100 on May 29, 2024. On May 30, 2024, the song reached No. 13 on the Billboard Global Japan Songs excl. Japan chart. Additionally, the song reached No. 3 on the Heatseekers Songs chart. In June 2024, the song ranked on Billboard Japan Niconico Vocaloid Songs Top 20' Half-year chart at No. 6 after releasing for five weeks.

It ranked No. 2 on the YouTube Japan Daily Top Music Videos chart on May 13, 2024. On May 22, 2024, it debuted at No. 5 on the YouTube Japan Weekly Top Songs chart. Additionally, "Mesmerizer" became the top-searched term on Nico Nico Pedia Weekly HOT Word Ranking on May 8, 2024.