Kojou Akatsuki's days as an ordinary high school student in the Demon District of Itogami Island come to an abrupt end after a fateful encounter leaves him with the remarkable abilities of a vampire. It isn't long before he is thrust into the center of attention when it is discovered that he is the fourth primogenitor, an immensely powerful vampire whom most consider to be merely a legend. Fearing Kojou's destructive potential, the Lion King Organization sends in an apprentice sword-shaman, Yukina Himeragi, to monitor, and should he become a threat, kill the boy deemed the world's most powerful vampire. Forced together by circumstance, the two form an unlikely alliance as Kojou comes to terms with his abilities and they both struggle to protect the city from various emerging chaotic forces. [Written by MAL Rewrite]

The second season of Strike the Blood which adapts three arcs from the 9th, 11th, and 12th light novel volumes.

It was announced at a Dengeki Game Festival stage event that the Strike the Blood light novel series will get a third OVA release. It will cover until the end of Seisen-hen. (Source: MAL news)

Thirteen-year-old Yasaka is a boy staying at his grandfather's house during his summer vacation. One day he entered a store and met Arashi, a beautiful sixteen-year-old girl working there. After trying to protect her from a man who claims to have been hired by her family to take her back by force, Yasaka ran away with her and now she stays at his grandpa's place with him. It didn't take much time for Yasaka to figure out that his new friend is far from an ordinary girl, as she possesses mysterious powers. The plot thickens when he finds a sixty-year-old picture of Arashi and another girl named Kaja, and to the surprise of all Kaja suddenly appears, and just like Arashi, her appearance hasn't changed at all since then. (Source: Wikipedia)