My wife is not what you’d generally consider an exhibitionist, but something about this little piece of clothing trips a switch inside her.
When you see her wearing one, it makes sense—her perky (natural) boobs and tight tummy seem made to be wrapped in a little stretchy piece of fabric. She looks ripe and perfect, ready to be unwrapped and devoured. Her wholesome girl-next door vibe (tall, athletic, blonde, glasses) somehow makes the whole effect ever hotter, and the visible bikini tan lines are the icing on the cake. Everyone stares—walking around the mall is an absolute trip—and we have so much fun with that.
Another benefit of tube-tops is they’re easy (and fun) to pull down.
On occasion if nobody is looking our way—say, we’re in an empty aisle at the supermarket—I’ll reach over without warning and just… casually pull her top down, completely exposing her tits. She blushes and giggles and scrambles to get it back up before someone appears. Ten minutes later her guard is down and I do it again. It’s a lot of fun and huge turn-on for us both.