Beth and I followed Mom into the house. It was strange and exciting to be totally naked, my cock coated with Mom's saliva and the remnants of my cum, with the two of them.
Beth glanced at me and chuckled, shaking her head.
"What?" I asked quietly. "What are you laughing at?"
My sister only shook her head and waved me off.
Mom sat down in her chair and spread her legs. She grinned decadently and beckoned. I headed toward her. "No-both of you," she commanded. We went and knelt in front of her. My cock had re-stiffened and bobbed in front of me, and I longed to grip it and stroke it.
"Since this is my birthday," Mom said and gazed at the two of us with a hungry gleam in her eyes, "I intend to be satisfied in ALL of my desires."
She shifted her attention to Bethany. "Come here, my dear," she murmured, smiling as Beth crawled between her legs. "I want you to lick me until I cum," Mom said, and looked at me. "And you can watch, but cannot touch yourself, is that clear?"
"Yes, Mom," I replied.
"What?!" she asked critically.
"Yes, Mistress!" I answered. My cock was already starting to throb. Not being able to touch myself was going to be murder.
Mom smiled and settled back into her chair. "Now, Bethany," she practically purred.
My sister flashed the strangest, softest smile and crawled forward and began to lap at our mother's pussy.
"Oh, that's very good, Bethany..." Mom sighed and shifted deeper into the chair. "Very good...".
My cock throbbed with need and I started to reach for it, but Mom stopped me with a sharp gesture and a look. I put my hands down and watched.
Bethany's ass and pussy faced me, and that made it even worse. Her shapely derrière sent electrical pulses through my body, from my penis to my belly. My cock bobbled, longing for a touch.
Mom smiled evilly and put her hands on Beth's head, drawing her in tighter, and she began to gently thrust her hips, her pussy, into Beth's mouth.
"You want to stroke yourself, don't you?" Mom asked low, amused. "Don't you?"
I nodded. "Yes, Mo-uh, Mistress."
Mom grinned and licked her lips. She lifted one of her lovely, massive breasts and licked her own nipple. She smiled even more wickedly when she saw my body's reaction.
"Lovely!" Mom chuckled and gazed at me as my sister continued lapping at her pussy.
It wasn't long before Bethany's licking and Mom's arousal reached a climax. Mom's attention went a bit distant as she started to writhe and moan. Finally, she gasped and arched, closing her thighs on Bethany's head.
"Ohhhhhh, fuck, yes...!" Mom sighed aloud as she came. She held Beth's head there for a long, long time, while she shuddered and climaxed several times. "Ahhhhhh...".
Mom sank back, releasing my sister from her place, and sat gazing at the two of us with a very indulgent glimmer in her eyes. She looked at me and asked, "And how are you doing, Mikey? Good? Is this hard for you?" She laughed and ran her hands over her body, chuckling as my eyes followed, drinking her in.
"What would you like to do?" Mom asked, and sat up, stretching. "Fuck me?"
I nodded, and my cock throbbed, making it bob and wiggle.
Mom moved to the edge of her chair. "Oh, I see...," she laughed. "And has this been a long time desire of yours?"
I nodded. "Yes, Mom. Mistress!" I corrected myself. Beth had stayed sitting on the floor, watching us and playing with herself idly, smiling at our exchange. Her lips were covered with Mom's juices, and I was envious.
Mom glanced at Bethany, and then back at me. "And I suppose you knew all about it?" she asked my sister.
Beth simply shrugged with a mischievous smile.
Mom sat back and looked me over. "Must run in the family..." she muttered quietly, with some private amusement.
"And you, little miss," Mom nudged Bethany with her toe. "Have you and your brother been 'experimenting'?"
Beth looked at her and shook her head. "No, Mom-honest. Michael and I have never had sex!"
Mom looked dubious and turned her attention back to me. "I am beginning to suspect," she said, "that you, Mikey, have been spying on me, haven't you? Like this morning in the bath?"
I nodded. My cock was achingly hard, and I really needed to touch it. Or have one of them do it for me.
"How long?" Mom asked, and stretched one of her legs out, showing me her wonderful, wet slit. She smiled when she saw my eyes immediately go to it. She put one hand down to it and began to caress herself. "You like watching me play with myself?"
I nodded. "Yes, Mistress!" I replied. My cock throbbed, waggling.
Mom chuckled and stroked her slit deliberately. "And did you jerk off while you spied on me?"
Again, I nodded. Beth sat so she could lean against the sofa and caressed herself, parting her legs so I could see her fully as well. My body was trembling with need, and I was dying. I needed touch!
"And did your sister know?" Mom asked.
I nodded.
Mom looked down at Bethany, staring at her with interest. "I see," she said. "And did your sister ever help you with your masturbation?"
I swallowed, but nodded. "Yes, Mistress."
Mom smiled strangely and settled back into her chair. She stroked her pussy and threw one leg over the arm, exposing herself more fully. "But the two of you never fucked?"
I shook my head. "No, Mistress."
Bethany paused, uncertain about where Mom was going with this.
"When I was your age," Mom said, a wistful expression coming over her as she caressed herself, "your Aunt Syvlia and I 'experimented' together." She paused and watched as my cock bobbed and throbbed in front of me. "We shared a room, and I was very shy and had no experience, and she offered to help me learn."
Mom paused and got more comfortable. She resumed touching herself as she recounted for us. Bethany also played with herself, intrigued by Mom's story. But me, I had to endure it, my body screaming for me to relieve it, to stroke myself.
"Sylvia had experience with both guys and girls, and I knew this. And I found myself feeling-flattered-by her telling me that she thought I was very sexy." Mom slid a finger into her pussy and fucked herself a few moments as she remembered. "She seduced me, your aunt!" she laughed. "And how!
"Sylvia started with a kiss. It was wonderful! It sent shivers through me! I had never felt so turned on before.
"Then she slipped her tongue gently into my mouth, and my pussy tingled at the sensation. Sylvia fondled my breasts, and removed my top. She kissed her way down to them, and I was a shivering, shuddering mess by the time she started suckling on them. She made me cum!
"But she didn't stop there. Your aunt pressed me back and kissed and licked her way down, down, down..." Mom paused, fingering herself again. She had a small climax, and opened her eyes. "Your aunt licked me until I came, and then she did it again. After that, she asked me if I wanted to lick her and I said 'yes'!" Mom laughed and looked at my sister and then back at me.
"We 'experimented' almost every day after that. Until she went away to college, though we'd resume when she came home for a visit."