Isekai de Konkatsu Hajimemashita

From MangaHelpers:

Yuka Hasegawa's cheating fiancé has broken up with her, and she falls on the stairs on her way home after hearing this shocking news. When she wakes up, she's in a new fantasy-like world, complete with knights, magic and royalty. She decides to become a maid at the nearby castle, in order to achieve her new goal of marrying into money. This decision kicks off her quirky love story!

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