It's going to happen and you know it. Just look at their eyes. They want the V. They don't care if they're sisters. That just makes it hotter. That old man is lucky. He has no idea what he's about to witness. He thinks he's about to witness a heart-touching long-lost sister reunion but little does he know, he's going to witness a sloppy, wet, lipsmacking fest between two sisters.
NOTE:: Notice how Tink's eyes shift up ever so slightly when Periwinkle looks a her. She was staring at Periwinkles tits :o