You can write about furniture that you see, imagine, or remember.
What makes a piece of furniture comfortable? Ugly? An heirloom?
Tables and couches are certainly furniture. Are curtains, counters, and closets furniture? What about a bathtub?
You can describe your shared history with a piece of furniture, or you can write about your imagined future together.
Be sure to give your work a title. Write the date on it, too.