It’s Yomu Mishima’s Mobseka Light Novel Fanfic .

Angelica Rapha Redgrave, the duke’s daughter whose engagement was broken as a villainess daughter of Redgrave Duchy. Approximately a year and a half after her conviction, she is offered a marriage proposal. The name of her fiancée is Leon Fou Baltfalt, a Baron. He is the second son of a poor aristocrat who achieved military prowess and wishes to retire. And she is the heartbroken digraced daughter of royal descent, what will be the outcome of this marriage proposal?