Eiji Hino (火野 映司 Hino Eiji) is an A.R. World version of Kamen Rider OOO from the World of OOO in the novel Kamen Rider Decade: World of OOO.
Despite often coming off as happy-go-lucky in his personality, Eiji is actually quite strong-willed and more clever than he lets on, and was easily able to pick up on the fact he could use Ankh's need for him and the OOO Driver to keep the Greeed in line. Another defining trait is Eiji will fight to protect anyone in need, even complete strangers and at the risk of his own life. This stemmed after his regret from not saving the little African girl he befriended during a civil war which his family fortune started. He keeps a collection of coins and almost always has pairs of underwear of different designs and colors which he at times even gives to others. This is revealed to stem from an optimistic outlook taught to him by his grandfather, who said that all a man needs is a pair of underpants for tomorrow.