Stern The Destructor  

Exterminator of Starlight, Material S, シュテル・ザ・デストラクター

Material-S is a material that belongs to the unbreakable system and was created during the Dark Fragment Incident by cloning Nanoha Takamachi. Her name, first mentioned in The Battle of Aces as "Exterminator of Starlight," does not have specific ruby-kanas. It's believed that the "S" in her name stands for "Stars" or "Starlight," which are associated with Nanoha. In The Gears of Destiny, it is revealed that her rubied name is Stern the Destructor, shortened to Stern, which means "Star" in German. Her device is named Luciferion.