The misadventures of Issei Hyoudou, a high school pervert and aspiring Harem King, continue in High School DxD New. As the Occult Research Club members conduct their usual activities, it becomes increasingly clear that something is amiss with their Knight, Yuuto Kiba, who is typically composed and alert. Issei soon discovers Kiba's dark, bloody past and its link to the mysterious Holy Swords. Having been the subject of a cruel experiment, Kiba now seeks revenge against those who wronged him. With the return of an old enemy and the arrival of two new beauties wielding Holy Swords, Issei and his Devil comrades are quickly drawn into another twisted plot.