The Devil Is a Part-Timer!: Emi Yusa

Her real name is Emilia Justina, she's the hero who fought desperately against the Demon Lord in her world, after forcing the Demon Lord to retreat from Ente Isla, she followed him to present day Japan to ensure that he is destroyed, but as the result, she lost her powers and was forced to live in modern Earth due to no way back to her homeworld and got a job as a call center agent. The reason why she hates Maou so much is because Lucifer, one of his generals, attacked her village and her people including the death of her father as her mother was an archangel. She later developed an relationship for Maou. These pictures are from Episode 6, I definitely remembered the scene she removed her sandals to put on slippers due to Chiho's school dress code. 

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