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The Tanabata (七夕) Family is one of the 18 Assistant Houses, bearing the number Seven (七) in their name.
They are part of 18 Assistant Houses, and are from the Seventh Institute, where the research focus was on anti-unit warfare. Their results are Herd Control Magics'. This in contrast to the non-militaristic Sixth Institute, and it was set up as a Magician Development Institute that took on the additional role of emergency capital defense. 
- Family Head