Your subbie sister is so excited to go to the play party tonight! She fantasizes about all of the play you both will get, and chuckles in wonder that Mistress is allowing you both to go after the stunt last week that got you both punished. Then you reveal the humiliating part...that while Mistress is allowing you to go the party - she's also locked you in a chastity cage! Your subbie sister is sympathetic...but it doesn't stop her from teasingly joking about miserable you'll be. Then it dawns on her! What if she helps you cum in your chastity cage before Mistress comes? That way you won't be in such pain at the play party! Your subbie sis gets to work, trying to think of all of the things Mistress does to you that you usually enjoy. She shakes her ass, wiggles her toes, and encourages you to play with yourself as much as you can around that pesky cage! Finally she gets bored and decides to let you watch her cum, and if you can cum while she plays with herself all the better for you! She shows off her hairy pussy, spreading it wide as she enjoys orgasm after orgasm.