Watch Strike the Blood: Kingdom of the Valkyria full episodes online enghlish sub
Other titler: Strike the Blood: Valkyria no Oukoku-hen
Synopsis: It was officially announced at the Dengeki Game Festival 2015 event that Strike the Blood will be getting a two-episode OVA series to be released at the end of 2015. The OVA will be an original story written by Gakuto Mikumo.
More info: Myanimelist, wikipedia