Tie them up for the evening

You let Sabrina take a shower back at your apartment and make a couple drinks for the both of them, perhaps they'll be a little looser and more playful that way. Sabrina comes out of the shower in a robe you're provided her just as the doorbell rings. You open the door to find Katherine standing there with a glare on her face, but looking as beautiful as ever. She glances past you to see Sabrina already in a robe, her hair wet.

"You've already had your way with my sister haven't you, you asshole," Katherine whispers angrily.

"Oh I haven't penetrated her pussy, her mouth or her ass yet today, we're just getting started," you reply smiling.

You give each of the sisters their drink and have them sit down on the couch. Once they've finished, you bring out the handcuffs and rope. Both of them protest immediately, although the drinks were strong and they're a little slower with their words. Sabrina puts up a little struggle as you try to handcuff her hands behind her back, so you shrug and move over to Katherine.

Katherine tries to slap you away as well but you grab her arms and ping them back, handcuffing her. You shove her down onto the floor and **** her legs together, tying them together as well. You shove a tablecloth into Katherine's mouth and then tie it around her head as a makeshift gag.

"Ok Sabrina, since you didn't like what I was doing, your sister is going to get a little spanking while you tie YOURSELF up. You better hurry cause the longer it takes the more punishment Katherine is going to get," you say.

Sabrina looks at you in disbelief, but you turn and smack Katherine's bare ass. Hard. Katherine gasps into the gap, her ass squirming in pain and you quickly follow up with another spank, just as hard. Seeing this, Sabrina quickly reaches for the rope and starts tying her legs together.

By the time Sabrina has managed to handcuff her own hands behind her back, Katherine has received at least a dozen spanks and is squirming on your carpet in pain, both her cheeks bright red. You do however detect a bit of moisture in between her thighs...naughty girl after all.

Both Sabrina and Katherine are now lying face down on your carpet, hands and legs tied, gags in their mouths, waiting to see what you do next to them.