Ryou is Alice Nakiri's aide. Originally, he owned a local pub within a port city in Denmark, where he also served as the executive chef. He was very controlling as an owner, having absolute authority in both the kitchen and to his customers. He met Nakiri Alice during her visit to Denmark and became her aide at some point after, although the exact details of when he left his restaurant is currently unknown.
Ryou ordinarily appears to be inattentive, lazy, and mostly subservient to Alice. Unlike Arato Hisako, he does often quip back at her at times and comments on her reactions in a deadpan manner, though the two are very close to each other. However, his demeanor changes when he puts on his headband - his passive expression gives way to a much more aggressive appearance, with sharp eyes and a mad, almost savage grin. In the manga, he had been described as a "mad dog" and a "dictator in the kitchen". Like Alice, Ryou is an exceptional cook, possibly even more so than even Alice by his own admission. He specializes in seafood, and his cooking has frequently been described as "violent" and "forceful", characterized by rich and sharp flavors. He considers the kitchen to be a battlefield between a cook and his customers, and believes that a chef should make a customer submit to his tastes. As such, he despises camaraderie among chefs, and is fiercely independent in his cooking.