Hayate Yagami (八神はやて)

Background

Eye Color: Blue
Hair Color: Dark Brown
Birthday: June 4
Intelligent Device(s):
Buch der Nachthimmel/Book of Darkness/Tome of Night Sky (Storage/Tome)
Schwertkreuz (Rod)
Reinforce II (Unison Device)

Mahou Shoujo Lyrical Nanoha A's

Hayate, a sweet wheelchair-bound orphan, is under the care of the Wolkenritter, though they keep their battles from her; she knows that the completion of the Book of Darkness will grant her vast power, but does not want it at the expense of the lives of others. However, the Book of Darkness is feeding off her own life force, causing her paralysis, and will eventually kill her if it is not completed... Hayate and Suzuka become fast friends after Suzuka helps her around the library, which may cause trouble if their respective friends learn that they have been fighting each other.

A's Epilogue

After the time-skip in the Epilogue Hayate has fully joined the TSAB along with Nanoha Takamachi and Fate T. Harlaown. Between A's and StrikerS it's revealed that Hayate had withdrawn from Earth schooling and relocated herself along with the Wolkenritter to Mid-Childa.

Mahou Shoujo Lyrical Nanoha StrikerS
Age: 19
Mage Rank: A (with Limiter), SS (after a limited release)
TSAB Rank: Lieutenant Colonel, Riot Force 6 Commander (Call Sign - Long Arch 0)

Hayate is a quiet and caring young woman who possesses one of the most fearsome Lost Logia that the universe has ever known. A partial release of her limiter giver her a SS rank (restricted to about A for routine operations in Lost Property Riot Force 6 due to bureaucratic limitations), she has a vast expanse of power that even the TSAB has trouble handling after ten years in the service. Lieutenant Colonel Yagami is the commanding officer of Riot Force 6, which she started, and is aided by Reinforce II, her unison device.

Mahou Shoujo Lyrical Nanoha ViVid

Mahou Senki Lyrical Nanoha Force

(Source: Nanoha Wikia)