Nothing, and no coverup either.

You look over the bikinis, trying to decide which one to wear. You eye the thong bikini, imagining how it would feel to wear it in public. Letting everyone see your body, almost completely on display. The thought turns you on, which makes you push your imagination further. You imagine being on the beach in that tiny, string bikini, with people of all ages checking you out. With all of them watching, you nonchalantly untie the top and pull it off, baring your boobs to the other beachgoers.

Naturally, the sight of a topless girl on the beach draws a crowd. In your fantasy, as the number of people watching you grows, you decide to go further. You make eye contact with your onlookers as you hook your fingers into the sides of your thong bottoms and yank them down to your ankles. You stand back up, presenting your audience with a full frontal view of your naked body. You soak in the attention as they all stare at your exposed flesh, some of them pulling out phones to take pictures. Since this is just your imagination, you happily enjoy it all without consequences. You shake your perky boobs for the crowd. You bend over and let them see you from behind. You sit down and spread your legs wide apart. You even slide a few fingers into your soaking, bare pussy.