The Lucky Boyfriend

Kirk came over to his girlfriend Jenni's place to surprise her.

He saw two other cars in the driveway- one that he recognized as her Stepsister Lori's.

Once inside, he hears some shuffling about and then a man meets him at the top of the stairs.

"I take it you're the boyfriend," he says.
"Uh yeah. And you are?"
"I was hired by your girlfriend for some boudoir pictures. I thought rope would look sexy and the other lady didn't agree.
Things got a bit out of hand...but you'll probably thank me."
"...um...what?"
"I won't charge her. Let Jenni know that."

He quickly rushes out with his camera and Kirk goes to the bedroom.
He hears moans and shuffling.

He opens the door to find his girlfriend tied up next to her Stepsister on the bed.
Both are naked and gagged, with rope marks showing earlier work done.

Kirk is confused and concerned.
He's also kind of horny at the sight of his naked girlfriend- the age of a MILF- and the sight of her Stepsister, who he's thought about before.

He goes to Jenni and takes her gag off.

"Um...surprise?"
"Let me untie you, honey."
A muffled retort comes from Lori, so he takes her gag off too.