Kosuke Nitoh is a major character in the tokusatsu series Kamen Rider Wizard, where he transforms into Kamen Rider Beast. Initially introduced as a mysterious rival to the protagonist, Kosuke is a lively and food-loving archaeologist who draws his powers from the Beast Driver, fueled by magical energy from Phantoms. He joins forces with Haruto Soma, the main Rider, and serves as both comic relief and a steadfast ally, providing crucial support in battles against the Phantoms.