After Miscarriage, I Sent My Ex-Husband to the Gallows

In medieval Aethelgard, Clora and Evelyn wed Fred and Victor. On their anniversary, ex Lise locks pregnant Clora in a burning manor. Fred and Victor save Lise's cat, ignoring Clora—she miscarries. Evelyn saves her. Husbands call her a liar, so they take revenge: Fred hangs, Lise is executed, Victor becomes a test subject. They rise to power.