Onihei
Origin: Spirits of the Past
Orb: On the Movements of the Earth
One: Kagayaku Kisetsu e
Our love has always been 10 centimeters apart.
Orange: Mirai
Otome wa Boku ni Koishiteru: Futari no Elder The Animation
Onmyoji
Only Yesterday
Oretachi ni Tsubasa wa Nai: Hadairo Ritsu Kyuuwari Zou!?
Over the Sky
Otoboku: Maidens are Falling for Me!