KoteIzu

KoteIzu is the slash ship between Kotetsu Hagane and Izumo Kamizuki from the Naruto fandom.

Canon
Kotetsu and Izumo are childhood best friends and partners, they are rarely(if ever..) seen without the other and hangout during and out of work. They are the front gate guards of Konohagakure and Tsunade's assistants.

Compared to Izumo, who loves to work and takes his job as a guard seriously, Kotetsu is more carefree and prefers to run off on the job to eat syrup(his favorite food). Despite their different personalities, they work well together and have great teamwork, as evidenced in their battle against Kakuzu and Hidan.

When Kotetsu runs off again during work shift to eat syrup in the Jōunin Standby Station, Izumo crashes into the room angrily and drags his partner back to work.

During the Chūnin Exams, they disguise themselves as genins together to assess the strength of the participating genins. They are later seen together(as chūnin) watching the genins take their test to make sure no one's cheating and later observing the preliminary matches.

They appear together again, when they discover Sakura knocked out after Sasuke leaves Konoha and inform the fifth Hokage.

Kotetsu and Izumo are teamed with Shikamaru and Asuma to hunt down an Akatsuki duo. They manage to track them down and by working together, they manage to land a hit on Hidan, but it was

Many other minor appearances together:
 * Guard duty
 * Carrying out a broken chair from Tsunade's office(which landed on Izumo apparently)
 * During Asuma's funeral

Trivia

 * Kotetsu doesn't take his job seriously because he and Izumo are basically Tsunade's "errand boys."