His favorite subject is Science, but having been brought up in the United States, Ryoma is fluent in English, which his classmates admire him for. He is also the object of admiration of his own fan club in school, which is led by Tomoka Osakada. However, he does not care about girls at this point in his life, due to solely focusing on tennis. His favorite color is silver although he is always seen wearing a red shirt and a red racket. His favorite racket is Bridgestone Dynabeam Grandea. In the manga, he is shown wearing Fila shoes, cap, wristband and shirt; in the anime, his hat has a "R" symbol on it. Ryoma is frequently seen drinking Fanta (Ponta in the anime).