Princess Romy is a fictional purple lioness or pantheress. Orphaned, she married an Indian Rajah devoted to the goddess Kali. After his death, she faced ritual execution by suttee on his funeral pyre. Rigodon intervened at great personal risk, rescuing her. With no ties left in India and threatened by religious authorities, she joined Willy Fog's traveling party, initially seeking relatives in Singapore. Discovering their demise, she stayed with the group. During the journey, she frequently served as a medic, tending to injuries.

Sustained interaction within the group, especially with Willy Fog, fostered her character development and a growing mutual attraction, though Fog maintained his composure. Upon reaching Britain, facing Fog's apparent failure to meet the critical deadline, Romy feared her presence caused damaging delays. Motivated by love and a desire to support Fog through potential financial ruin from losing the wager, she proposed marriage. Fog accepted.

This proposal indirectly secured the group's success. It prompted Rigodon to realize their eastward travel gained them a day, providing just enough time to reach the Reform Club and win the bet. After victory, Romy, believing her original reason for the proposal was void, suggested ending the engagement. Fog, having developed deep affection and gratitude for her companionship and actions, refused. They remained married.

In subsequent official media, she appears as Willy Fog's wife. Visually, she consistently wears a long dress or skirt, often obscuring her feet. When visible, her feet are bare, small, and three-toed, matching the anthropomorphic style. Her veil, initially black during her rescue in India, changed to white for the remainder of the journey.