The 23-year-old singer and the 35-year-old actor decided to ham it up for the cameras after they spotted the photographers nearby.
Demi was also spotted taking a dip in the water and removing her swimsuit, which she also wore the day before, at one point!
The couple was seen the day before showing off a whole lot of PDA and even recreating the Dirty Dancing water scene in a romantic moment.
35+ pictures inside of Demi Lovato in St. Barts with Wilmer Valderrama… More Here! »