Isekai Tensei Shite Majo ni Natta no de Slow Life wo Okuritai no ni Maou ga Nigashite Kuremasen (Light Novel)

Miya was a career woman who works hard as a talented secretary. But one day she lost her life and reincarnated as demon Miya in a different world! She got a job at Demon Castle and worked hard as a secretary again, but she retired from electric shock after giving up on the Demon King who handles Miya too much. To live as a witch Miliyam in the human world. Miya was a knight and a disciple who lived a leisurely slow life in the human world, but the Demon King attacked!?