If there's something that will indicate that a girl is definitively making sure that she spends most of her time in the outdoors, absorbing a whole lotta vitamin D, that's tan lines. I mean sure okay, they can go around in a shirt and shit like that, I feel you. However, most girls will not do that. They'll hit the beach in a bikini first thing in the morning, and they'll chill around like that, and if they have a nice body, they'll truly be a great sight. These are the kind of girls that won't hit the water during the entire day. Naw, they'll just lay down on their back or on their belly, trying not to make their titties hurt while they lie down, and they'll just sunbathe all day. Though, when their bikini is off, the color of their skin will look amazing with the tan lines.