The misadventures of Issei Hyoudou, high school pervert and aspiring Harem King, continue on in High School DxD New. As the members of the Occult Research Club carry out their regular activities, it becomes increasingly obvious that there is something wrong with their Knight, the usually composed and alert Yuuto Kiba. Soon, Issei learns of Kiba's dark, bloody past and its connection to the mysterious Holy Swords. Once the subject of a cruel experiment, Kiba now seeks revenge on all those who wronged him. With the return of an old enemy, as well as the appearance of two new, Holy Sword-wielding beauties, it isn't long before Issei and his Devil comrades are plunged into a twisted plot once more.

Kazuma Hoshino is preparing himself for a new stage of his life as a teenager. Because of his brother Ayumu's weaker than average health, their parents thought it best for the family to move out from the city to a more rural environment. Now the two brothers are off to the Yorozuyo Inn where they’ll be staying until their parents can settle affairs back in the city and set up their new home. Their arrival to the inn doesn't go as planned though when they catch the wrong bus, wind up in the middle of nowhere, Ayumu gets his hat stolen by a wild monkey, and Kazuma gets lost in the woods trying to track the animal down. It all leads to a chance encounter with a spirited young girl named Ui, who Kazuma ends up accidentally falling onto and kissing while she tries leading him back to the bus stop. This hardly sits well with Ui’s friend Ibuki who swiftly kicks Kazuma and sends him on his way. Much to Kazuma's continued horror, his bad luck is perpetuated at the inn thanks to its landlady Senka and her slightly perverted sense of humor, and then finding out that two of his classmates are the girls he embarrassed himself in front of back in the woods! Hoshizora e Kakaru Hashi finds Kazuma adapting to his new school, dealing with the multiple women who have entered his life, providing emotional support for his younger brother, and coping with living with his new landlady. However, for some reason, something about this place is bringing whispers of the past into Kazuma's mind. Small flashes back to a more innocent time and a friendship long forgotten. What could this déjà vu mean?

When an extraterrestrial organism known as Savage attacks mankind, the only technology capable of combating the enemy is a weapon known as “Hundred.” A survivor of a Savage attack, Hayato Kisaragi is a teenager boasting the highest compatibility level with the aforementioned technology and as a result, is invited to master his skills at Little Garden, a prestigious military academy aboard a battleship. Over the course of his intense training for the battle ahead, he immediately attracts the interest of multiple female peers and gets drawn into a number of incidents as he tries to fight against the creatures that now inhabit Earth and threaten its safety.

OVA bundled with Niθ Art Works Vol. 2, featuring a new character named Kagekatsu Uesugi.