She doesn't have to

As it turns out, Ms. K's massive black dildo is a double-headed affair, saving her the trouble of selecting only one option.

First, she lubricates one end of the thick black plastic cock, then without any warning, presses it up against your exposed hole. You jump in surprise, but your head is being held close to Erica's snatch, and Ms. K is firm and decisive in shoving the enormous dildo into your ass.

Erica even grips your head tightly in both hands as Ms. K pushes half a foot of thick plastic cock into your rectum, ignoring your muffled protests.

Erica's voice sounds amused, yet slightly disappointed as she addresses Ms. K.

"I have admit that wasn't what I was expecting."

Ms. K laughs, lightly tweaking the dildo in your ass.

"You sound a little put out, but don't worry, this one's meant for sharing."

You feel Ms. K slide her other hand upwards, leaning her weight onto your back to keep you pinned to the bed.

Erica looks more closely at the half of a dildo still protruding from your ass and you can almost hear the grin in her voice.

"Oohh...I see."

Erica slides her pussy out from beneath your mouth while Ms. K grips the back of your neck in one hand and the middle of the dildo in the other, keeping you in place with a surprising amount of strength.

A few moments later, you feel the dildo in your ass shake about as Erica places the other tip at the entrance to her pussy and starts to insert it.

She's not used to taking anything so thick, but her pussy is well-lubed, and before long, you feel her take the entire length inside.

Erica's groin bumps into your ass from behind as if she's fucking you, and the stimulation of her movement keeps making the dildo instead you grind against your prostate until pre-cum starts dribbling out.

It's hard to concentrate on anything other than the dildo shifting about in your ass, but you hear Ms. K chuckle as she continues holding you down.