Aldnoah.Zero Gaiden: Twin Gemini

A pair of Martian Knight sisters from the Vers Empire, operating a Kataphrakt unit, arrive in a town in Sapporo, Hokkaido, at the same time that Slaine and Trillram head to New Awara to join Inaho and the others. The town is home to the twin siblings Mizuki and Haruya Mikage.