Ane no Koto ga Sukina Hittou Majutsushi-sama ni Migawari de Totsuidara, Naze ka Watashi ga Dekiai saremashita!? ~Munou Reijou wa Kuni Ichiban no Kekkai Majutsushi ni Kaika suru~

Thetis, a countess, has been compared to her superior older sister and treated as incompetent by her family.

One day, she receives a proposal of engagement from Noah Savoid, the most famous magician in the country.

She wonders why she, who is so inconspicuous, should be asked to marry him. She wonders, “Noah loves me, but I have a fiancée, so he can't marry me. You should comfort him at best,” she tells him cruelly.

She marries into the Savoid family, but what awaits her there is the best of hospitality and overflowing doting love from Noah...⁉

A love story of a dedicated hero and a doting duke.