Mahoutsukai no Konyakusha

Went looking for magic but found love instead...

Filimena via Adina, daughter of nobility, awakens one day with the realization that she had actually been reborn into a world of sorcery and given a second chance at life. In her new country full of heroes, she expects this means she's a chosen one, yet her lot is not as she dreamed—instead, her path crosses with the improbably powerful stepson of a wizard, and as a young noble lady, her place is at his side...as his fiancée! But perhaps a quest for love is exactly the adventure she was looking for...

(Source: Yen Press)