|Okai Chisato promoting "℃OMPLETE SINGLE COLLECTION"|
|Also Known As||Chissaa (ちっさー?)|
|Born||June 21, 1994|
|Occupation||Idol, Singer, Actress, Model|
|Agency||UP-FRONT AGENCY (2002-2012)|
UP-FRONT PROMOTION (2012-)
|Associated Acts||℃-ute, Hello! Project Kids, Athena & Robikerottsu, Tanpopo#, Mellowquad, Triplet, H.P. All Stars, Mobekimasu, Stelladrop, Okappy, Okaileage|
|Member Color|| (2009-2017) Green|
She was a member of Little Gatas until she was added to Gatas Brilhantes H.P.. She was also a part of the unit Athena & Robikerottsu consisting of Okai, Niigaki Risa, Mitsui Aika, and Nakajima Saki in 2007. They sang the opening and ending theme song for the anime Robby & Kerobby.
A video of Okai covering the dance for Dance de Bakoon! was uploaded to ℃-ute's Official Youtube Channel. It achieved 100,000 views in 2 days; upon reaching 500,000 views, ℃-ute's new single Aitai Lonely Christmas was released in celebration.
On November 27, Okai became the first member of ℃-ute to get her own single and a separate listing on iTunes. Before the year ended, she released two more songs on iTunes.
On January 24, Okai released another song on iTunes. The Solo Live 2011 Vol.1 ~Kaisha de Odotte Mita!~ was also released. The CD contains two songs from her iTunes list, while the DVD has singing and dancing of 12 songs.
On July 4, Okai and Ishikawa Rika starred in a mini drama titled "Tokusou Shirei! Aichi Police". Okai also starred in a stage play featuring Nakajima Saki, Miyamoto Karin and Kudo Haruka. titled 1974 Ikunayo.
On March 2, at SATOYAMA e Ikou! ~Forest For Rest~, Okai was announced a member of the new SATOUMI movement unit, Mellowquad, along with ℃-ute member Yajima Maimi and Berryz Koubou members Tokunaga Chinami and Natsuyaki Miyabi.
On April 1, it was announced Okai would have a regular Thursday segment on CBC’s Go Go Smile.
On March 26, it was announced Okai would be a regular on the TV show Haraichi no Kami Appli.
On June 21, Okai celebrated her 20th birthday at a special event called ℃-ute ~Okai Chisato Birthday Event 2014~. The event featured two performances in Tokyo.
On June 20 and 21, Okai celebrated her birthday in a special fan club tour called Cutie Kankousha Fanclub Tour "Okai Chisato Birthday Party" in Nagano.
On July 24, it was announced that Okai Chisato would be a regular on TV Tokyo's Chou Shiritoriaru. The show ran from August 3 to August 24.
On August 13, Chisato appeared on the TV show VS Arashi as part of "Team Saitama".
On June 22, Okai celebrated her 22nd birthday at a special event called ℃-ute Okai Chisato Birthday Event 2016, featuring one performance at Differ Ariake.
On July 7, she announced on her blog that the surgery was successful. However, after consulting her doctor, Okai could only participate as an MC for the first three Hello! Project 2016 SUMMER shows on July 16 and 17, but returned to fully performing for the following concerts.
- Main Page: Family of Okai Chisato
Okai has 4 sibilings: two younger sisters, Asuna and Mion, and two younger brothers, Tsubasa and Rimu. Asuna is a former member of Hello Pro Egg. Her father runs a small plumbing business. She is also the aunt of Asuna's child. 
Okai currently owns 2 dogs: Lipstick and Howl. She previously owned a dog named Pine, who passed away in 2013. In July 2016, her family got another dog named Pants. She also owns 4 turtles, which includes Elizabeth and Kamedo.
The following list are notable friendships Okai Chisato has acquired:
- Hagiwara Mai: Okai is good friends with Hagiwara Mai.
- Nakajima Saki: She is good friends with Nakajima Saki.
- Suzuki Airi: She is good friends with Suzuki Airi.
- Yajima Maimi: She is good friends with Yajima Maimi.
- Tsugunaga Momoko: She also is good friends with Tsugunaga Momoko from Berryz Koubou and often mimics her.
Here is a list of nicknames that was used to refer to Okai Chisato:
- Chissaa (ちっさー): Official nickname, given her since joining ℃-ute. Used by members and fans.
- Okai-chan (岡井ちゃん): Official nickname. Used by members and fans.
- Name: Okai Chisato (岡井千聖)
- Birth Date: June 21, 1994
- Birthplace: Tokorozawa, Saitama, Japan
- Nickname: Chissaa (ちっさー), Okai-chan (岡井ちゃん), Chisato (ちさと), Chippe (ちっぺ)
- Blood type: A
- Height: 152cm
- Weight: 42-43 kg 
- Western Zodiac: Gemini
- Eastern Zodiac: Dog
- Hello! Project Status:
- 2002-06-30: Member
- 2005-06-11: ℃-ute member
- 2017-06-12: Left (℃-ute disbands)
- Years in ℃-ute: 12 Years
- Official Kaomoji: ﾘ ・一・ﾘ
- ℃-ute Color:
- Blue (2006-2009)
- Green (2009-2017)
- Audition Song: "Country Roads" from the anime movie "Whisper of the Heart"
- Hello! Project Groups:
- Shuffle Groups:
- Hobbies: Watching movies, collecting purikura
- Special Skill: Getting along with anyone
- Strong Point: Making everyone laugh
- Weak Point: Fooling around too much
- Habit: Walking like a crab
- Favorite Color: Blue, light blue, brown
- Favorite Flower: Cosmos and sunflower
- Favorite Movie: The Terminator, Backdraft, Nankyoku Monogatari.
- Favorite Book: Shonen Magazine.
- Favorite Word: "Nice"
- Favorite Season: Summer and winter
- Favorite Food: Asian pears, kalbi kuk bap, sushi
- Least Favorite Food: Eggplant
- Favorite Song: Uwaki na Honey Pie and GET UP! Rapper
- Charm Point: Eyes
- Looks Up To: Fujimoto Miki, Sayashi Riho
- [2010.11.27] LOVE Namida Iro (LOVE涙色) (Matsuura Aya cover)
- [2010.12.10] Manatsu no Kousen (真夏の光線 ) (Morning Musume cover)
- [2010.12.10] Egao ni Namida ~Thank You! My Dear Firends~ (Matsuura Aya cover)
- [2011.03.29] Furusato (ふるさ) (Morning Musume cover)
- [2012.02.02] Tokai no Neon ga Odoroku Kurai no Utsukushisa ga Hoshii (都会のネオンが驚くくらいの美しさがほしい; I Want To Be Beautiful Enough To Overshadow the Neon Lights of the City)
- [2012.04.18] Kimi wa Jitensha Watashi wa Densha de Kitaku (君は自転車 私は電車で帰宅; You Ride Your Bicycle, While I Catch the Train To Get Home) (C-ute cover)
- [2013.04.03] Kanashiki Heaven (悲しきヘブン; Sad Heaven) (Okai Part Ver.)
- [2011.02.25] Solo Live 2011 Vol.1 ~Kaisha de Odottemita!~ Live in Heaven (会社で踊ってみた)
- [2011.04.18] Solo Live 2011 Vol.2 ~Hanzomon de Odottemita!!~ (半蔵門で踊ってみた)
- [2013.10.26] Chisato Okai Birthday Event ~last teenage~ (岡井千聖バースデーイベント～last teenage～)
- [2014.09.26] ℃-ute Chisato Okai Birthday Event 2014 (℃-ute岡井千聖バースデーイベント2014)
- [2015.03.26] C-ute Suzuki Airi・Okai Chisato FC Event 2015 (℃-ute 鈴木愛理・岡井千聖FCイベント2015)
- [2015.08.27] Cutie Kankousha Fanclub Tour "Okai Chisato Birthday Party" in Nagano
- [2016.xx.xx] ℃-ute Suzuki Airi Birthday Event 2016
- [2016.xx.xx] ℃-ute Okai Chisato Birthday Event 2016
- [2017.01.26] ℃-ute Suzuki Airi・Okai Chisato FC Event 2016
- [2010.12.22] Chisato
- [2010.10.05] Alo-Hello! C-ute (アロハロ！℃-ute) (Chisa version)
- [2012.03.06] Cutest (Chisa version)
- [2012.10.22] Alo-Hello! C-ute 2012 (アロハロ！℃-ute 2012) (Chisa version)
- [2012.03.30] Hello! Project 2012 WINTER Hello☆Pro Tengoku Live Shashinshū ~Rock-chan & Funky-chan~
- [2015.07.11] Hello! Project Maruwakari BOOK 2015 SUMMER
- [2016.01.02] Hello! Project Maruwakari BOOK 2016 WINTER
- [2013.07.18] Weekly Famitsu Taiwan vol.444
Featured on the coverEdit
- [2011.03.xx] Confetti vol.075 (with Nakajima Saki)
- [2011.12.xx] Confetti vol.084 (with Nakajima Saki)
- [2012.04.11] D-GIRLS ~The dancers of social media~ (Mook)
- [2013.04.06] Top Yell (with Michishige Sayumi, Tanaka Reina, Tsugunaga Momoko, Iikubo Haruna, Fukuda Kanon, Hagiwara Mai, Fukumura Mizuki, Ishida Ayumi, Sayashi Riho, Oda Sakura)
- [2013.06.28] Anikan R Yanyan vol.7 (with Suzuki Airi and Hagiwara Mai)
- [2013.08.06] Top Yell (with Berryz Koubou [Main feature], Suzuki Airi, Fukuda Kanon, Takagi Sayuki, Takeuchi Akari, Miyamoto Karin, & Uemura Akari)
-  Koinu Dan no Monogatari (仔犬ダンの物語)
-  Hotaru no Hoshi (ほたるの星)
-  Ousama Game (王様ゲーム) (as Maruoka Kaori)
-  Gomennasai (ゴメンナサイ)
- [2002–2007] Hello! Morning (ハロー! モーニング)
- [2007–2008] Haromoni@ (ハロモニ@)
-  Berikyuu! (ベリキュー!)
- [2008–2009] Yorosen! (よろセン!)
- [2010–2011] Bijo Gaku (美女学)
- [2011–2012] Hello Pro! TIME (ハロプロ！ＴＩＭＥ)
- [2012–2013] Hello! SATOYAMA Life (ハロー！ＳＡＴＯＹＡＭＡライフ)
- [2013–2014] GOGO! Smile! (ゴゴスマ)
- [2014–] The Girls Live
- [2014–] Haraichi no Kami Appli (ハライチの神アプリ)
-  °C-ute no Challenge TV (℃-uteのチャレンジTV)
- [2015–2016] Afro no Hen (アフロの変)
-  Chou Shiritoriaru (超シリトリアル)
-  Tokusou Shirei! Aichi Police (特捜指令！アイチ★ポリス) (as Mai)
-  Suugaku♥Joshi Gakuen (数学♥女子学園)
-  34 Choume no Kiseki -HERE'S LOVE- (34丁目の奇跡 -HERE'S LOVE-)
-  Neruko wa ℃-ute
-  Keitai Shosetsuka
-  Atarumo Hakke!?
-  Akuma no Tsubuyaki
-  1974 (Ikunayo) (1974(イクナヨ))
-  Sengoku Jieitai
-  STRONGER (ストロンガー)
-  Theater in The Round (青山円形劇場)
-  Sakura no Hanataba (さくらの花束) as Koyamada Mei (小山田芽以)
- [2010–2012] Okaichan, Neru! (岡井ちゃん、寝る!)
-  Michishige Sayumi no "Mobekimasutte Nani??" (道重さゆみの『モベキマスってなに？？』)
- [2013–] Hello! Project Station (ハロ！ステ)
-  Tokai no Hitorigurashi (都会の一人暮らし) (Radio drama)
- [2016.10] HELLO! DRIVE! (HELLO! DRIVE! -ハロドラ-) (Fridays)
1st Event (2008.06)Edit
- Ganbacchae! by Morning Musume
- Ekimae no Dai Happening by Fujimoto Miki
2nd Event (2008.09)Edit
- Koi no Hana by Abe Natsumi
- Bishoujo Shinri by ℃-ute
3rd Event (2009.04)Edit
- Robokiss by W
- Zutto Suki de Ii Desu ka by Matsuura Aya
- Big dreams by ℃-ute
4th Event (2009.11)Edit
- Bokura no Kagayaki by ℃-ute
- As ONE by ℃-ute
- ONLY YOU by Zoku・v-u-den
- EVERYDAY Zekkouchou! by ℃-ute
5th Event (2010.04)Edit
- ONLY YOU by Zoku・v-u-den
- Watarasebashi by Matsuura Aya
- Hajimete Kuchibiru wo Kasaneta Yoru by Matsuura Aya
- Koi no Jubaku by Berryz Koubou
Rankings & MilestonesEdit
- She ranked 4th in a magazine's 2011 "Girls that seem like they'll become big stars in the future". 
- She ranked at #38 in Anikan R Yanyan magazine's May 2013 "Singing idol you like the most".
- She ranked 9th in mixi's June 2013 Hello! Project Popularity Ranking.
- Has said Fujimoto Miki is the Hello! Project member she respects the most.
- Miyamoto Karin thinks that Chisato is the coolest member of Hello! Project.
- She often plays "Mario Kart" with the ℃-ute members.
- She was the first member of ℃-ute to get her own single and own listing on iTunes.
- Was the last active member of ℃-ute to release their first photo book.
- Okai's audition song was "Country Roads" from the anime movie "Whisper of the Heart."
- She has a scar on the right side of her nose. She said she got it before joining Hello! Project.
- She was known as a "tomboy" in the early years of ℃-ute while she had short hair.
- She became very popular with posting dance videos on ℃-ute's YouTube account (ocutechannel).
- Okai was the first member of ℃-ute to dye her hair brown. She first had it dyed around the time she joined Hello! Project Kids.
- Okai sometimes says that she looks Brazilian because of her naturally tan skin.
- Okai is scared of ghosts.
- Okai is the only current member of ℃-ute with type A blood.
- She is the shortest member in ℃-ute.
- Claims that she has dog eyes.
- In Team Okai, she covers Sayashi Riho.
- Okai and Yajima Maimi are the only two current Hello! Project members who are still in Gatas Brilhantes H.P.
- Okai says she wants to appear on lots of variety shows to get people to know her.
- Stated that she thinks Natsuyaki Miyabi has a wonderful smile.
- She thinks Natsuyaki Miyabi is cute.
- She has admited to being "in love" with Hagiwara Mai during her first few years in ℃-ute.
- She and Kanazawa Tomoko are the two current Hello! Project members with the most siblings (with 4 each).
- Three days after turning 20 she tried her first alcoholic drink.
- She stated that she would like to visit Britain because she loves castles and other things from the country.
- Gallery:Okai Chisato
- List:Okai Chisato Discography Featured In
- List:Okai Chisato Concert & Event Appearances
- Side:Family of Okai Chisato
Okai Family TreeEdit
- ↑ 1.0 1.1 Hello! Morning. Broadcast Date: 2002-06-30.
- ↑ Tsunku. "『Berryz工房』（ベリーズこうぼう）誕生について" (in Japanese). Tsunku Official Website. 2003-01-15.
- ↑ Tsunku. "℃-ute （キュート） に関して" (in Japanese). Tsunku Official Website. 2005-06-11.
- ↑ http://natalie.mu/owarai/news/154763
- ↑ "VS嵐♡岡井千聖" (in Japanese). ℃-ute Official Blog. 2015-07-17.
- ↑ "ご報告です。岡井千聖" (in Japanese). ℃-ute Official Blog. 2016-05-29.
- ↑ "℃-ute 岡井千聖に関して" (in Japanese). Hello! Project. 2016-05-28.
- ↑ "報告です！ 岡井ちゃん" (in Japanese). ℃-ute Official Blog. 2016-07-07.
- ↑ "℃-uteに関するお知らせ" (in Japanese). Hello! Project. 2016-08-20.
- ↑ "Announcement concerning ℃-ute." UP-FRONT LINK. 2016-08-20.
- ↑ https://twitter.com/dmny1009/status/766659914630467584
- ↑ "今後について。岡井ちゃん" (in Japanese). ℃-ute Official Blog. 2017-05-27.
- ↑ http://ameblo.jp/c-ute-official/entry-12206555589.html?utm_source=dlvr.it&utm_medium=facebook
- ↑ " 【℃-ute】岡井千聖の身長や彼氏の噂は？かわいい画像も大量にまとめ！に投稿された画像" (in Japanese)
- ↑ " 岡井千聖のカップと彼氏を大公開！！" (in Japanese)
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