Uraurashima

Uraurashima a.k.a. Reverse Urashima (English manga) is a member of the Fractured Fairy Tales. He fights Kurama in the Semi-Finals. He tricks Kurama into believing that he's fighting against his will, and uses the Idunn Box (Reverse Treasure Box) in an attempt to turn him back into a helpless baby before killing him. The magic works too well however, turning Kurama back into the ruthless Yoko thief, who attempts to torture him to learn the secrets of the Idunn box. He was killed by Shishiwakamaru when he threw his sword into the barrier and impaled him in the neck before he could tell. He is then revealed to be a disguised lesser demon. His character is based on the tale of Urashima Tarou.