I Attended My Ex-Fiancé's Wedding and Found My True Love

Konyakusha ga Asu, Kekkon Suru Sou Desu.
婚約者が明日、結婚するそうです。

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Konyakusha ga Asu, Kekkon suru Sou desu.
婚約者が明日、結婚するそうです。
novel

Lane, who lives in a small village far from the capital, hears that her fiancé, who left five years ago, is marrying a saint. She had already given up hope, so she doesn't feel anything. For some reason, he seems to want to invite his childhood friends to the wedding. Unable to refuse the invitation from the royal castle, Lane finds herself attending the wedding of her fiancé and the saint. In the capital, where she travels with a heavy heart, she meets someone, and her fate changes dramatically. A happy-ending romance in which Lane, who was living in misfortune, finds true love. (Source: Tsugikuru, translated)