Middleton, who has gained much media attention in the wake of her older sister's wedding to Prince William, was photographed with friends in Madrid on Friday night.
The former couple was seen at The Penthouse in Spain partying with friends until about 4 a.m. Middleton was wearing a beige skirt, black jacket and stilettos for her night on the town, according to MTV UK.
The 27-year-old was also seen enjoying a boat trip with Percy in Retrio Park the next day.
This could mean that Middleton may be following in her sister's royal footsteps. She and Percy, who is the son of the Duke of Northumberland, met while studying at The University of Edinburgh.
However, it was also reported that Middleton is in a relationship with ex-cricketer Alex Loudon.