Ryoma Echizen (越前 リョーマ, Echizen Ryōma?) is a fictional character and the protagonist of the anime and manga series The Prince of Tennis. Ryoma is the son of Nanjiro Echizen, formerly known as 'Samurai Nanjiro' during his days as a former professional tennis player and of Rinko Takeuchi-Echizen, a sweet tempered attorney. Ryoma gains the nickname "Samurai Junior" later in the series. He makes his first appearance when he criticizes a high school student about his tennis knowledge. As the main character, Ryoma is among the most popular characters in the series.

In the fourth Shonen Jump character popularity poll of series, Ryoma came in third place.

Source: Wikipedia