Popsugar Celebrity Halloween Costumes 2019 Celebrity Couple Halloween Costume Ideas 2019 25 Celebrity Couples You and Your Significant Other Can Be This Halloween 19 September 2019 by Kelsie Gibson View On One Page Photo 9 of 25 ADVERTISEMENT () Start Slideshow Share This Link Copy ← Use Arrow Keys → 9 Serena Williams and Alexis Ohanian at the Met Gala What to wear for Serena: A yellow gown with pink floral appliques. What to wear for Alexis: A black and white tux with a bow tie. Previous Next Start Slideshow Halloween Costumes 2019Celebrity CouplesHalloween Costumes