Your sister Lissie has been acting strange, today before she took off to the pool she fingered herself in front of you like it was nothing and then took off like nothing! then when she came back she did it again! only this time she did in front of your dad also, she fingered herself till orgasm and then went to her room, you and your dad decide this needs to be talked about so you both go into her room to talk about her inappropriate behavior, she just brushes you both off and pulls out her brother's dick and rides it... then she switches to her father and she just keeps going back and forth till she comes! when she's done she fixes her outfit and says bye and leaves as if nothing happened while you and your dad are both left confused but wanting more.