Byleth and Felix were engaged to be married soon after the Battle of Fhirdiad. The war against those who slither in the dark was long and arduous, but they found solace always in one another. When the fighting was finally done, they held a modest wedding ceremony and entered a new life together as husband and wife. Where they went afterward is not known, but it is widely believed that they traveled the world as mercenaries, side by side, blades in hand.