Hinekure Koushaku wa Noroware Otome ni Kudokareru

Eclair, the daughter of the Billot family, one of the four Great Ducal Houses of the kingdom, is a Magic Knight with an outstanding academic record at the magic academy.

One day, she was participating as a guard in the ceremony to select the Princess's fiancé. As the ceremony proceeded, a magical tool worn by the Princess suddenly exploded. Eclair, who shielded the Princess, was covered by a mysterious magic circle. Mistral, the head of the Tamon family (another of the Great Ducal Houses), rushed in to help, but Eclair's body had shrunk—?

The key to breaking the curse is marriage with the twisted Duke!? A love fantasy spun by two complete opposites!