"You look at other cues. What they're doing, their expressions, what they look like and how they interact." Heiji tilted his face in the direction of a middle-aged woman making her way across the beach. She moved aside when a gaggle of teenagers in spaghetti-strap swimsuits came by.

"Like that lady. A little older, more conservative, she's got a hat and sunglasses on and a big old bag for keeping things. Not the kind of person who'd go around baring it all in public, right? But she still looks put together, prepared. Probably got a black one piece."

And indeed, when she sat down and primly shrugged off her top to apply some sunscreen, this prediction was apparently true.