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Jussai no Saikyou Madoushi (十歳の最強魔導師, The strongest ten year old magician) is a 2016-Present webnovel/light novel series by Amano Seiju.
The series is about a 10 year old girl named Ferris (フェリス Ferisu) who escapes from her life of slavery in a mine. Upon arriving at a town she ends up rescuing a girl of nobility, Alicia (アリシア・グーデンベルト Alicia Guudenberuto), from being kidnapped. Ferris is taken to Alicia's home to rest, and Alicia's family discovers that Ferris possesses extremely powerful magical potential. To protect Ferris, as well as prevent Ferris from bringing disaster to the world, Alicia's family takes her in.