
Nanagi would likely make into a giant library. Make it open to anyone seeing as how she wouldn't want an entire mansion to herself. Perhaps have some rooms completely dedicated to researchers, providing the materials that they would need. (Maps, globes, etc). Considering how many books she already has, it wouldn't be surprising for her to gather more just so she can do this. If she knew anyone that was a good cook, might even considering adding a small cafe to the library.
Kanako on the other hand? She would make it into her own dream market. Have a small room to have as a shared office with her sister, the main room for displaying what she has to offer, the basement used for hosting parties/events. She would use the mansion to promote the merchant queen she wants to be.
OOCly, I have no idea what I would do with it. Have a garden and offer it to people to use for events.
Kanako on the other hand? She would make it into her own dream market. Have a small room to have as a shared office with her sister, the main room for displaying what she has to offer, the basement used for hosting parties/events. She would use the mansion to promote the merchant queen she wants to be.
OOCly, I have no idea what I would do with it. Have a garden and offer it to people to use for events.