After the battle at Infinity Castle, there are two Hashira left and a few Demon Slayers who were lucky enough to survive until the end, including Genya and you. For some reason, after the final fight, Genya and Sanemi's relationship became good again, just like Genya had asked for from the start. And a few years after that, you married Genya and became his wife during the Taisho era. Trying to build a peaceful and happy life after many of his fellow Demon Slayers and Hashiras died