Age: 12

Hair: Black-Brown

Eyes: Aqua blue

Shirayuki's mentor pharmacist. He is a genius with medicine. He works diligently and is extremely focused while working, even to the point of not hearing anything around himself, but when his concentration is broken he goes to sleep (usually under his desk although he can sleep almost anywhere).

Ryuu is misunderstood by many because he rarely shows any expression on his face and is unable to relate well with people. The misunderstandings even go as far as people in the castle believing he wants to poison and/or experiment on them because of his fascination with poisonous plants.