Ouji Kosaka

Ouji Kosaka (also spelled Kousaka Ouji; Japanese: 高坂 王子) is a supporting character in Future Diary (Mirai Nikki).

He is a classmate of the protagonist Yukiteru Amano (Yuki), who previously bullied and teased him in school. During the deadly Diary Game/Survival Game, Ouji initially betrays Yuki (such as during a key incident), but he later becomes an ally and friend to Yuki's group.

Ouji ends up connected to the game through a special diary (the "Apprentice Diary" or "Kosaka King Diary"), which predicts "brilliant moments" for him or those around him. He is portrayed as somewhat cowardly, opportunistic, and not particularly skilled in combat or strategy, often relying on others.