Somewhere further than making out yet not quite going all the way, "fooling around" is a time honored tradition. It's easy, low-pressure, and there are no real parameters - above the clothes or not. Sound good? Maybe you're young and want to try but not commit to anything too carnal. Similarly, you could want to explore somebody's, well, body because they're so different than you. There's also the possibility that you want to make them happy or see how they react to feeling beyond great. Could it be that you're a tease, even?
Or you could just be bored. There's nothing on TV, anyway.