OiKage

OiKage is the slash ship between Oikawa Tooru and Kageyama Tobio from the Haikyu!! fandom.

Canon
Kageyama and Oikawa were teammates in Tobio's past team in Kitagawa Daiichi Junior High. Tooru was Kageyama's Senpai back then and was the one who taught him a lot of techniques, which Kageyama still uses to this day. They met again in episode 7 of the first season. After Aobajohsai High lost to Karasuno High School's team - of which Tobio was a member - in the same episode, Oikawa set himself a goal to defeat Karasuno next time, especially Kageyama.

Fandom
FAN FICTION
 * Tooru/Tobio tag on FanFiction.Net
 * Tooru/Tobio tag on FanFiction.Net