Koyanagi Misa (小柳美沙) was born July 24,1998.Koyanagi is the curret leader of the Hello!Project Duo group,Y.okatta,and a former second generation member of the Hello!Pro Kenshuusei.
Koyanagi is also featured in the units: a.o.i and H2-O.
In 2007,Koyanagi made her official debut as a second generation Hello!Pro Kenshuusei member.
In June 2009,after the formation of S/mileage,Tsunku wanted to do another Hello!Pro Kenshuusei group.Tsunku said he was going to have a pratice test with the Kenshuusei (meaning he was going to watch them sing and dance,and chose which ones should form the group).Koyanagi (alongside Matano Maho) was chosen to debut,forming the duo group Y.okatta.
August 25,Y.okatta's debut single,Hinihini Onna noko,Yoru wa Heroine! was released.Koyanagi was a main vocalist for the song.
In May,it was announced that Koyanagi was chosen to form the group a.o.i,alongside Morning Musume member Michishige Sayumi and Berryz Koubou member Shimizu Saki.
September 8,it was announced that Y.okatta,Hello!Pro Kenshuusei member Takagi Sayuki,and former Morning Musume member Nakazawa Yuko would be participating in the stage play,ICHIDO Jinsei no Jikan de (Once in A Life Time).The stage play ran from September 12-September 18
July 23,Koyanagi held a fanclub event for her birthday,under the title Koya=naasan!.
At the Hinafest,it was revealed that Koyanagi was chosen to form the SATOUMI unit H2-O,alongside S/milegae member Katsuta Rina and Juice=Juice member Takagi Sayuki.
- Name: Koyanagi Misa (小柳美沙)
- Nicknames: Koyana (高野数),Koya-nyan(高野ニャン),Misachan(みさちゃん)
- Birthplace: Tokyo,Japan
- Birthdate: July 24,1998 (age 15)
- Bloodtype: O
- Hello!Project Status
- 2006: Hello!Pro Eggs Member
- 2009-06-14 Egg Graduated
- 2009-06-14 Y.okatta Member
- UP FRONT PROMOTION Status
- 2009-06-14 Member
- Y.okatta Member Color: Orange
- Hobbies: Shopping & Going to Disneyland
- Dislikes: Algebra
- Favorite Food: Almost Everything!
- Least Favorite Food: Squash
- Singing Level: High!
- Dancing Level: Medium
- Favorite Color: Green & Blue
- Looks Up To: Michishige Sayumi & Shimizu Saki
- Hello!Project Groups:
Singles Participated In
- Hinihini Onna noko,Yoru wa Heroine! (Debut)
- YOKATTA DUO
- Tsuyoku Naru
- Care (less)
- KEEP IT UP! (Indies)
- Utsukushii (minikuimasen!)
- Aa,Watashi No Ai
- Omoikiri Tanoshimu
- Suppin HATARAKU!/The Best Wishes
- Amai ASIA!
- AH! Aoi Tori!
- SHIROI TORI
- Waratte ne...
- Busu ni Naranai Tetsugaku
H.P SUPER IDOLS
- Dakishimete Yo,Boat Man! / Hai! Watashi no Kazoku! (with DOUBLE X)
-  DOWNTOWN!
-  ICHIDO Jinsei no Jikan de
-  Wide Awake Dreams (as Hinako)
- [2010-2012] Misa to Maho ~YOKATTA!~ (as Herself)