Ryuuji Adamura (阿多村竜二, Ryuuji Adamura) is the second eldest son of the Adamura family and the new successor to the Bunokura Mine following the murder of his brother Ryuuichi.
Ryuuji is described as a tall man and looks aggressive and intimidating. He is quick to anger and not very perceptive, as demonstrated when he forgets information provided to him by Isozaka minutes earlier regarding Izaya's age and family. He has been noted for to think lowly of his half-brother, Kazuhisa, for being the son of a prostitute and frequently bullies him.
After Ryuuji hears that Izaya and Douma Kiyojima have met up somewhere and that Douma was returned unharmed, he assumes the two must have teamed up and even considers the possibility the two have a part in his brother's death. He calls his father and requests the assistance of Candiru and Usubara to track down and eliminate Izaya.