The Prince of Tennis is primarily set in Tokyo, and centers around Ryoma Echizen, a tennis prodigy who attends Seishun Academy, a school known for its strong tennis club and talented players. Ryoma quickly defeats numerous upperclassmen shortly after entrance to secure himself a spot as one of the team's regulars.

Spritle and Chim Chim are an inseparable team. They often pop up at just the right time to pull Speed out of a jam, but also have a disconcerting habit of sneaking inside the Mach 5's trunk.

In Eyeshield 21, Sena Kobayakawa joins the Deimon Devil Bats football team as its running back. To protect his identity from other teams who want to recruit him, Sena is forced to publicly assume the role of the team secretary and enter the field under the pseudonym of "Eyeshield 21" wearing a helmet with an eyeshield to hide his features.

The series starts with Ash Ketchum's tenth birthday, which according to Pokémon trainer registration bylaws allows him to become a full-fledged Pokémon trainer and obtain a starter Pokémon.