Despite his flirtatious nature and childishness, Oikawa is an excellent, well-rounded player and is extremely serious about volleyball. He's known to have a "disgusting personality" amongst both opponents and his own teammates because of his smug and outwardly flippant attitude. However, on more than one occasion, Oikawa has been very attentive and caring of others. Oikawa is ambitious and one-track-minded, but he also has feelings of inferiority towards those he sees as naturally more talented.