Yu is the protagonist of Persona 4.

In the Persona 4 Arena duology, Yu has also shown to be a fairly sarcastic person and occasionally makes jokes at the other Investigation Team members' expense, but he is, for the most part, the most mature of the group (most notably is the fact that attempts to target his personal insecurities by enemies, more often than not, fall flat). He has a sharp mind, and is able to quickly realize the trick behind the tournament that forces the group to fight one another. He deeply cares for his friends and one of the few ways to truly anger him is to threaten either them or Nanako which causes him to become very cold. He also has a great understanding of the bonds of people, which lead Aigis and Mitsuru to realize that despite their different appearances, Yu reminds them of the protagonist of Persona 3. He does notably trust Yosuke completely and generally understands him best out of the entire Investigation team and vice versa. This continues the theme that the anime established that in the entire Investigation Team, Yu and Yosuke are closest with each other and generally lead the team side by side, as well as discussing plans with each other on serious issues.