Video Game / Kingdom Days
Kingdom Days is a Dating Sim by Pacthesis that you can find here.

Rose Urwin (or whatever you call her) is the princess of the Lunar Kingdom. Ever since she was found by her parents, Sakka and Lilla, in an orphanage and brought to live in the castle, her life has been one of ease, especially with her personal servant and childhood friend, Lewis Ashton. However, that all changes when the castle is attacked by enemy soldiers and she and Lewis are forced to flee. They escape to the neighboring kingdom of Hepcatsis, where they meet the king, Joseph Knight. He only allows them to stay when Lewis impulsively offers Rose's hand in marriage to him, which he accepts (much to Rose's dismay).

Problem is, he immediately departs for an unknown destination just the day after, leaving behind only a note saying he'll be back before the wedding, which takes place in thirty days. Those thirty days are enough for Rose to find love in Hepcatsis with either Lewis, Daniel Claud, Ian Leroy, Ferris Vidal, or Joseph himself when he returns.

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