Friendly Rivalry

Not all rivalries are bitter. Some are actually quite friendly with both parties getting along very well. The rivalry usually manifests in a competitive drive to one up each other with both parties developing their talents. If the rivalry involves people of the opposite sex, there is always the possibility of them becoming more intimate with each other.

Can be related to Friendly Enemy depending on the circumstances.

Anime and Manga

 * Tycho Science and Princess Lal'c in Aim for the Top 2! Diebuster. As the top two ranked pilots they constantly traded friendly jabs at kill counts.
 * There are a number of examples in Naruto
 * Naruto and Sasuke (pre-time skip) as members of Team 7.
 * Sakura and Ino become this upon Sakura's discovery that Ino also has a crush on Sasuke.
 * Guy and Kakashi, as proclaimed (multiple times) by Guy. Kakashi, true to character, is rather apathetic about the whole thing.
 * Though only vaguely alluded to, the reader gets a sense that Jiraiya and Orochimaru had a relationship much like the one shared by Naruto and Sasuke.
 * Eyeshield 21: Sena has friendly rivalries with both Shinn and Panther; in the case of the latter the two of them are practically friends, despite being on opposite teams. The same can be said of Ootawara and Kurita, and Sakuraba and Monta; one gets the feeling that if they played at the same school they would be the best of friends. Quarterback Youchi Hiruma isn't particularly civil to anyone, but his rivalries with Ojou quarterback Takami and Seibu quarterback Kid is about as close as he gets. He and Hakushuu quarterback/safety Marco verge on Friendly Enemy.
 * Harlem Beat: Kuwata from Yotsuya Unohara team has no qualms about teaching Naruse or conversing about team management with Kobayashi; both from rival team Johnan.
 * In Mahou Sensei Negima, Negi has this relationship with Kotaro. Likewise, his father Negi has this relationship with Jack Rakan.
 * In the manga incarnation of Higurashi, this is the way Mion thinks of Keiichi. She also has a major crush on him too.
 * Ichigo and Ishida of Bleach become this after some time.

Video Games

 * Flynn and Yuri in Tales of Vesperia.
 * Unlike previous rivals in Pokémon, some of the rivals in future generations (Wally in Ruby/Sapphire and Cheren and Bianca in Black/White) are very friendly towards the protagonist.
 * In Soul Nomad and The World Eaters, Danette is Revya's childhood friend/rival. In her ending (male), it is heavily implied that they will become intimate.
 * Ryu and Ken of Street Fighter, obviously.
 * Sakura and Karin, too (mainly in Alpha 3 and Namco X Capcom).
 * Despite his denials, Mao and Raspberyl of Disgaea 3 Absence of Justice are friendly rivals.
 * A friendly rivalry between the protagonist and Jamie in Harvest Moon Magical Melody is possible. Since Jaimie is always the opposite sex, the option of marrying him/her is always an option. Doing so lands you a rare Nonstandard Game Over good ending.
 * This is apparently the relationship that Tails and Yoshi have in the Mario & Sonic series.
 * As well as with the main duo Mario and Sonic themselves.
 * And Peach and Amy; Daisy and Blaze; most of the rivalries in the games... However, it's averted with Luigi and Shadow, who spend most of the time on-screen glaring at each other.