Key is a Japanese visual novel studio and is located in Kita, Osaka, Japan. In addition to developing visual novels, they have also helped to create anime not only based on their existing visual novels, but also original anime titles.
Official website: http://key.visualarts.gr.jp/

 
6.0
Planetarian: Chiisana Hoshi no Yume

 
7.0
Clannad: Hikari Mimamoru Sakamichi de – Jōkan

 
5.0
Clannad: Hikari Mimamoru Sakamichi de – Gekan

 
7.0
Tomoyo After: It’s a Wonderful Life

 
8.6
Little Busters!

 
7.8
Air

 
7.0
‎duplicate Little Busters!

 
4.0
Kanon