The Princess and her Knight

The setting is your own kingdom (your home). One partner plays the beautiful princess who, tired of the royal duties, is longing for a thrill. The other partner transforms into the brave and charming knight, visiting the kingdom and looking forward to demonstrating his valor.
The knight respectfully requests a royal feast with the princess. This gives you an excuse to prepare a dinner theme and have fun cooking together or assembling a meal from whatever you have on hand.
As the evening progresses, the princess expresses her desire for some entertainment, and the knight must rise to the task. You make up challenges for the knight to accomplish. These can be as innocent or sensual as you desire, growing more intimate as the night progresses.

Start by preparing your wardrobe. The princess can don a simple, flowing garment like a dress or robe, whereas, for the knight, a smart casual outfit should be fine. Anything that speaks to the theme will work. A tiara and a pretend sword, if you have them, can add an extra touch of authenticity.
Next, set up your royal dining area. Create a medieval-inspired dinner with dishes such as meat, cheese, raw fruits, and vegetables, and if you do have wine in the house, it can be the perfect drink. Use candles for lighting to create that classic renaissance atmosphere.
Lastly, prepare a list of challenges or tasks the knight must accomplish. These can be simple and funny tasks, gradually escalating to romantic or seductive actions.

Immerse yourself in the characters and the time period you're portraying. Allow yourself to step out of your regular roles in your relationship and instead, embody the characteristics of a medieval princess and her knight. The more committed you are, the more fun it'll be.
Don't shy away from any awkward moments. Transform them into laughter and continue with the roleplay. Remember, you're in your own kingdom and it's all about having fun.
Finally, keep in mind this isn't about perfection but creating a memorable, intimate experience. Be patient, be communicative, and simply enjoy the journey of emulating these royal characters.