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Natsuki Karin
SynthV Studio

Natsuki Karin (夏色花梨) is an upcoming Japanese vocal to be developed and distributed by TOKYO6 ENTERTAINMENT in collaboration with AH-Software Co. Ltd., and is expected to release as an AI voice database for Synthesizer V Studio. She is also expected to release as a speech voicebank for CeVIO AI.

Karin is expected to release in April 2022.

She is voiced by Miyu Takagi, a Japanese voice actress.


Natsuki Karin is a third-year student attending the fictional Otaru Shiokaze High School. She can play the bass and is noted to be "not good with troublesome things". When she was in the first grade, she was a guitarist and vocalist, but after Koharu Rikka joined the music club, she turned to the bass.

Karin likes double fromage, archery, and cute things. She dislikes matcha.[1]


Natsuki (夏色) translates to "summer color" or "the color of summer". Karin (花梨) refers to Chinese quince fruits and fruit trees.


Karin is a high school student with shoulder-length, mauve-colored hair tied into pigtails and black bows tied at the top. She has pale purple eyes with a mole under her left eye.

Karin wears a standard school uniform - a white top with a purple bow and a dark blue/white accented long sleeved partially opened jacket over it. She also wears a short, dark blue, pleated skirt, black and white-striped thigh-high, and a pair of brown loafers.

Ekaterina (エカテリーナ), her companion, is a mauve-colored stuffed bear with tall ears, small black horns and black claws. She wears a dark black ribbon tied to her chest and has a small black bow on her head. She has a pair of black bat wings on her back.


  • Ekaterina - Stuffed bear companion
  • Koharu Rikka - fellow student & music club member at Otaru Shiokaze High School.
  • Hanakuma Chifuyu - fellow student & music club member at Otaru Shiokaze High School.


Natsuki Karin was introduced in a campaign titled "Koharu Rikka x Otaru Collaboration (小春六花×小樽コラボ)" on May 22, 2021. She was confirmed to be a student enrolled at the fictional Otaru Shiokaze High School and was in the same music club as Koharu Rikka.[2][3] Details about Karin as a character were released and she was confirmed to be voiced by Miyu Takagi for a promotional video.[4][5] She was illustrated by Teshima Nari and the logo was created by Hiroaki Watanabe.[6] It was noted in a TOKYO6 ENTERTAINMENT livestream that there were plans to create a voice library for Karin and Hanakuma Chifuyu, which were confirmed in June to be Synthesizer V AI and CeVIO AI after TOKYO6 ENTERTAINMENT adjusted their website.[7]

On August 8, due to some concerns regarding business activities related to Synthesizer V, Dreamtonics Co., Ltd. noted that Karin was on the list of "yet-to-be-published" voices and initiatives.[8] For many overseas fans, this was the first time they became aware of these voice databases as there was no official announcement via social media nor newsletter of the productions and website adjustments. Due to language barriers, the livestream featuring the announcement was also overlooked. On September 30, a livestream was confirmed to begin on October 3.[9]

On October 3, it was confirmed that Karin would be produced as the second TOKYO6 character to release. Demonstrations of her Synthesizer V AI and CeVIO AI voice databases, along with a set of Pitagoe samples, were released in addition to an announcement of her crowdfunding campaign, which was set to begin on October 8 and would run until October 28.[10] Separate illustrations for Karin's Synthesizer V and CeVIO designs were also revealed.[11] Karin was expected to release in April 2022.[12]

On October 8, Karin's crowdfunding campaign was launched with a goal of 6,800,000 yen.[13] The main goal was reached in less than three hours since launch, then the final stretch goal was reached on October 11.[14]

Voice Database Information[]



あの星を探して (Ano Hoshi o Sagashite) - Short Version YouTube Twitter
イエナイコトバ (Ienai Kotoba) - Short Version Niconico YouTube Twitter

Voice Databases[]

Product Information
Package details as noted:
Information pending.

Phonetic notes as noted:
Through cross-lingual singing synthesis, Karin AI is able to sing in not only Japanese but also in English and Mandarin Chinese. This feature is only available in the Synthesizer V Studio Pro Editor.

License agreements as noted:

Voice Libraries[]

  • Natsuki Karin Talk Voice (CeVIO AI), In development
  • Natsuki Karin AI (Synthesizer V Studio), In development

Additional Information[]


On May 22, 2021, Karin received an official acrylic keychain.[15] A cocktail collaboration with Bar V, a bar in Susukino Sapporo, was also announced.[16] On May 24, three contests as part pf the Koharu Rikka x Otaru Collaboration were launched one of which was to name Karin's and Chifuyu's stuffed bear companions.[17] Finalists of the Otaru Collaboration radio FM, Mascot Name and Audio Drama contests were announced during the second TOKYO6 ENTERTAINMENT Official Live Broadcast on July 21. Twelve entries were submitted for the stuffed bear mascots for Karin and Chifuyu respectively. Of the winning entries, Ekaterina (エカテリーナ) was selected by Miyu Takagi, Karin's voice actress, as the name for Karin's mascot submitted by Twitter user Kagamin.[18][19]


Natsuki Karin's character status
Upon revelation of Koharu Rikka's companion characters, Natsuki Karin and Hanakuma Chifuyu were met with excitement as the second and third new characters of TOKYO6 ENTERTAINMENT's line. This led to anticipation and hope that the pair would receive voice databases in the future. In June 2021, their productions for CeVIO AI and Synthesizer V AI were officially confirmed via livestream, but as the video was available only in Japanese, the lack of announcement via social media, and no notification of a website update, many overseas fans did not become aware of the production until August that year. Regardless, fans were excited to know that the two would be joining Rikka as voice synthesizer characters.


External links[]