They Summoned Her From 21st Century To Save Them

One evening, as Sei Takanashi returns home from a long day at work, a magical force pulls her into a foreign world. Upon her arrival to the kingdom of Slantania, she overhears that the Grand Magus inadvertently summoned two Saints-Sei and a brown-haired girl. Needing only one holy maiden, the prince declares the other girl as the Saint, leaving Sei to her own devices.
Anime - The Saint's Magic Power is Omnipotent (Seijo no Maryoku wa Bannou Desu)
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