Kirihito Kumon was a young man from the real world and he found himself in a new world of Duel Monsters so he heads up on a journey through the dimensions with Yuya and the others.

Meeting Seto Tenjo. A 18 years old young man who found himself in the virtual world known as Underworld, in order to finding a young girl named Alice in Underworld. So, he joins Kirito and Eugeo to set on a quest to finding Alice at the Central Cathedral and also his silently makes a vow to defeat his arch-rival Kirito when the time is ripe.