Long before we married, my wife Amy was constantly cooking, cleaning, and sexually servicing her older sisters, and her stepfather.
She was told she had to earn her keep and she never complained.
Her sister Brenda had always taken advantage of Amy to do her chores and such. One day she found a better use for Amy. She had a huge strap on dildo that was also a vibrator. Her job was to lick her sister's pussy until she was good and wet and then strap on the vibrating dildo and pump her sister while kissing her and sucking her tits until she came.
Both have huge tits. Amy has bigger, more succulent breasts, while Brenda does has big tits, her plump pale white ass is what all the guys love about her.
There was a great advantage to this, since the vibrating dildo's base was specifically designed to vibrate against Amy's clit so Amy always reached orgasm many times while pumping her sister with the strap on.
There was one other caveat. The dildo was uniquely designed to hold a good amount of liquid in a reservoir that was pressurized (kind of like a super soaker - the more Amy pumped in and out of her sister's pussy, the more pressure would build up).
Amy would fill it up with warm water and once Brenda was close to orgasm, she would push a button on the back of the dildo strap that would squirt and blast the contents of the reservoir deeply and forcefully into her pussy.
After Brenda would finish she would head for the bathroom where Amy would draw a bath for her sister and bathe her and bring her to climax again using the water that came rushing out of the faucet. Amy would sit behind her sister and pinch Brenda's nipples while Brenda's wide open legs would receive the rushing water against her clit.
Things changed a bit once Amy and Brenda's mom remarried.
The stepdad – Mark, moved in with his daughter who had unnaturally enormous watermelon tits (you have to see to believe – Amy later told me they were a size 44FF. The best part is her waist line is very thin in comparison so she looks like a cartoon character. Amy says her breasts weigh more than both her breasts combined, and hers are huge). Not too long after the honeymoon new rules were set in the house. (A lot of it had to do with the fact that Amy's mom was pre-menopausal and was not in the mood for having sex. This pissed Mark off since he didn't get married to be celibate).
The 3 girls had daily chores to perform. The chores were evenly rotated and no one performed the same duties 2 days in a row.
* 1 girl would cook, prepare breakfast, lunch and dinner.