Ryuji is known as a disruptive "problem student" at school whose bad behavior causes all sorts of trouble for the teachers. He is quite proud of his status as a self-proclaimed "troublemaker" and his rebellious, mischievous and disobedient nature are the perfect qualities to be a Phantom Thief. He can sometimes be vulgar and aggressive, as shown in his early interactions with Yusuke and Makoto. He is also rather short-tempered, easily taking offense from even the slightest of comments. That said, he will never resort to violence, unless he is provoked.  He is very straightforward when it comes to expressing his feelings, especially in regards to his hatred of selfish adults and authority figures who abuse their power. He is deeply empathetic when it comes to the plight of others; simply listening to Ren's story of how he got arrested makes him extremely angry, and hearing about Kamoshida's sexual abuse greatly upsets him.  

Ryuji can be clumsy and overly energetic sometimes; he has a habit of yelling constantly, despite frequent warnings from Morgana  to keep his voice down, which usually results in loud outbursts that often includes accidentally revealing himself and his friends as the Phantom Thieves. This, combined with his frequent density, causes him to be viewed as an idiot by his peers, Morgana in particular and makes him as some sort of comedic relief in various situations. Ryuji also occasionally has a hard time accepting blame for things, though it's less he doesn't recognize when he's at fault so much as he hates being held solely responsible for an incident when he feels he isn't the only issue, or if it was simply beyond the group's control. 

Set to appear in;

- The Daybreakers

- Dark Sun

- Stars and Ours

- A Magical Valentine's Day

To have an idea of how Ryuji should sound, this should help: https://www.youtube.com/watch?v=_FPXrR_8qoo