A former member of The Dirty Dawg and the leader of the Ikebukuro Division team, Buster Bros!!! The eldest of the three Yamada brothers. He is characterized by heterochromia, with a red left eye and a green right eye, and has a single beauty mark under his left eye. At 19, he is the proprietor of Yorozuya Yamada. True to the name "Yorozuya" (Jack-of-all-trades), he takes on a wide range of requests, from shopping and finding lost cats to gathering underground information. He is a man of justice who cannot abandon those in trouble, and is beloved by the residents of Ikebukuro. However, because he was once a delinquent so famous that no one in Ikebukuro didn't know his name, he is still occasionally challenged to battles by thugs. He has a fundamentally serious and reliable personality. Even during his delinquent days, he would refuse alcohol and cigarettes when offered, showing that his core integrity never changed. (However, if he deems it necessary for work or an emergency, he will use underground routes without hesitation as a practical means, which is why he is still considered a former delinquent boy.) He possesses the charisma to be admired by others and has been praised for having a natural talent for leadership. He disciplines himself to look forward, believing that making excuses is wrong and complaining is unlike him. In that sense, he has a mature air beyond his years, but he can get quite heated if his buttons are pushed, showing he is still a 19-year-old at heart. He is the pillar of the Yamada family, and the Yorozuya office and his home are located in the same building. As the eldest son, he has a very strong sense of responsibility. He is strict in raising his younger brothers so they can grow into capable men, and perhaps due to the environment he grew up in, he is a pure athlete/physical type. However, he is also primarily responsible for cooking daily meals, and he has a side that worries over menus to ensure his growing brothers eat nutritious food. In this way, he loves his brothers more than anyone as a brother, father, and mother figure, but he does not admit to having a brother complex and is the type who doesn't usually say "I love you" to their faces. Additionally, he is actually an otaku who loves anime, manga, and light novels.

As per official settings.

As per official settings. Calls Ichiro "Ichi-nii." Calls Jiro "Low-IQ" or "Jiro." Never says anything to disparage or look down on Ichiro. He loves Ichiro.