The Legend of Oppai Dragon and his Lively Companions (おっぱいドラゴンと愉快な仲間たちの伝説 Oppai Doragon to Yukaina Nakamatachi no Densetsu) is the fourth (and current) story arc in High School DxD. The story arc began in Volume 14, with Volume 13 being a series of side stories and Volume 15 a combination of side stories integrated into the plot.