Los Feliz Jason Behr, Kadee Strickland Gelson's The heiress must be prepping for bikini season!

Paris Hilton and her beau River Viiperi attended a pilates class in Studio City yesterday, and the Simple Life star looked a little exhausted from her toning session when we caught her leaving the studio.

Speaking of studios, Princess P's new pop album for Cash Money Records is almost done! "I'm in the studio and almost finished with the album. They're just finishing up all the paperwork and there will be an announcement soon," she recently told The Daily Beast.

That's not the only project on the blonde beauty's schedule, though!

The reality star just opened her 44th Paris Hilton store, launched her 15th fragrance, and, on top of it all, is set to open a hotel property in Manila next year.

She's the hardest working woman in show biz!