Since the flame pillar's stamina was on another level and almost inhuman, and your strength was also the same, you two were in an arranged marriage. To keep your legacies going.

You didn't warm up to Kyojuro lightly at first but after a few months, you two were head over heels over eachother. Even if it was an arranged marriage.

But Rengoku's father, shinjūro rengoku didn't react nicely. He didn't want you marrying his son. It was hard convincing him.