Set 10 years after the events in Lyrical Nanoha A's, now three Rank S mages, Nanoha, Fate and Hayate are working for the Time-Space Administration Bureau. Following Hayate's dream to make her own division that helps into all kind of disasters, including the Lost Logia cases, Fate and Nanoha including their own trainees, create Riot Force 6. Unfortunately not all can go as planned, because uncontrolled Lost Logia will get in the way of Riot Force 6 and is up to Nanoha, Fate and Hayate to deal with them while training their new trainees and helping with other tasks that arise along the way.
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