The smooth, cool satin of their panties teases their sensitive flesh, awakening desires they've long suppressed. They circle each other, like predators stalking their prey, each waiting for the other to make the first move. The air is thick with tension, the weight of their secret pressing down on them. Yet, they can't stop, can't turn back from the edge of this precipice. They're sisters, yes, but tonight, they're also lovers, bound by silken threads of lust and desire.