Ritchie is a young boy, friend, and rival of Ash Ketchum. He teamed up with Ash to get the Pokémon back which were stolen. He was then forced to battle Ash in the Indigo League and defeated him, early in the series. Once in Johto he helped Ash save a baby Lugia and its mother from the clutches of the notorious Team Rocket. All of Ritchie's Pokémon have nicknames with the exception of Eevee. He was present in Pokémon Chronicles and has not been seen since. He is same age as Ash.
Sparky is Ritchie's Pikachu who is usually seen out of its Poké Ball. It was able to defeat Ash's Charizard after it was lazy.
In Pokémon Diamond and Pearl, during the contests, there is a contestant named Luis. He seems to be based on Ritchie because of his outfit and having a Pikachu nicknamed Sparky.
Ritchie mentioned in Oaknapped that he and Ash tend to catch the same Pokémon.
Ritchie deisgn is similar to Red from Generation I, he is a pallette anime swap for Red, the differents Red clothes are Red & White Jacket, Shoes, and Hat, while having blue pants, Ritchie has Blue & Yellow Hat, Green Jacket, Pants, possibly Blue, Green, or Purple Shoes, the point this that he wear the outfit as Red do in Generation I not Generation III on Generation I.