Christina Aguilera is planning a “sexy” Las Vegas show. The 43-year-old pop star is currently preparing for a residency at The Venetian Resort’s Voltaire, and the show is set to be her sexiest in years. A source told The Sun newspaper: “She’s kept a very low profile in the run-up to the gigs in order to maintain her health, but it’s safe to say things are going to go off with a bang. “The show will be classic sexy Christina with an impressive set and dancers, but it will never take away from her voice. “The venue is smaller than many in Sin City but that’s not stopped her going all out. “The s…