Sisters and Brother

"Promise." Marge echoed Lisa.

It was the one binding oath that we all kept, I revelled in my victory and let a small smile appear on my face.

"You'll teach me everything?" I asked "Even about lesbian sex?"

"Even" Lisa gulped "about lesbian sex. Marge and I will show you how it works, won't we Marge."

"Uh, yes, we'll show you." Marge agreed reluctantly.

"And I can experiment with you?" I asked.

"Yes." Lisa nodded.

"What's the catch?" I asked "I know, its only for a day or something."

"No," Lisa protested "we are not setting a time limit. It will be up to you to say when we have finished teaching you."

It was all that I had hoped for and more, I let them squirm for a few more minutes while I 'thought' about their offer, there had never been any doubt that I would accept, but they didn't know that.

"Okay," I said at last "I accept your offer. When can we start?"

"Now if you like." Lisa smiled "What would you like to learn first?"

"I'd like to know how a woman sucks a man's cock Lisa and I want you to teach me first." I grinned.

As Lisa lowered her head to take my cock into her mouth I sighed, sat back and started planning my future lessons.