As I snuck into the bathroom, I kept thinking how incredible Aunt Linda looked in nothing but a strap-on, and couldn't wait to see her fuck my mom with that realistic looking dong of hers. I suddenly realized that I hadn't come all day. It was time to let loose.
I silently opened the door, amazed that no one could hear the thundering of my heart beating a mile-a-minute. I peeked in just as Aunt Linda was opening the shades to let in some light so I'd be able to see them. My mom was lying on her back masturbating, apparently she didn't bother to stop this time when her sister came into the room.
"What have you got there, Sis?" Aunt Linda climbed onto the bed.
"A towel I found in the hamper." My mom lifted it to her own face. "It has my little boy's cum on it." She held it out to her sister, who drew in the scent of my dried semen.
"Mmm, I'll bet it tastes good when it's fresh and warm."
"Oh, it does, Linda, it does." Mom moved the towel down between her legs and rubbed it against herself. "My son's cum tastes so good to me, I want it so bad. I want him to come in my mouth right now."
"Would you share some with your big sister?" Aunt Linda caressed my mother's chest, squeezing and rubbing her big tits.
"Yes," Mom breathed, "I want you to know how good my baby's cum feels in your mouth." She released the towel as her sister's hand reached down there and she slipped a finger inside my mom's pussy. "Aah, that feels so nice. But I want him inside me. I want to feel my boy's hard penis in my pussy again."
"Maybe this will do instead." My aunt brandished her fake cock and my mom took notice of it for the first time.
"Ooo, you came to fuck your little sister with your big cock?" My mom grabbed it and stroked it experimentally. "Where did you get this thing?"
"My daughter got it for me last Christmas. Rachel loves it when her Mommy fucks her tight, little pussy with it."
"I want you to fuck me, Sis. Fuck me just like you fuck your daughter. Fuck me like I want my son to fuck me."
"Then get up on your hands and knees, bitch!" Aunt Linda gave Mom's pussy a hard smack, that brought out an involuntary yelp.
I was peering through the narrow space at the door and going out of my mind. I had planned on waiting until they really got into it before I started jerking, but they were getting wild right out of the gate. I tugged the loose skin of my ball sack in an attempt to distract me from my urge to stroke off immediately.
"Like this?" Mom was up on all fours across the bed sideways, her head facing toward me. I had an excellent view of her huge tits dangling down, but I couldn't quite see exactly what Aunt Linda was doing behind her. Worse yet, I couldn't open the door any wider or Mom would spot me. I tried to calm my breathing and just watch and enjoy whatever I could see.
"Spread your knees, slut. Let me see that hairy pussy of yours." Aunt Linda maneuvered behind my mom as she followed her sister's commands and opened herself up wider. My aunt bent down and spit on my mom's pussy, and used the head of the dildo to spread it around.
"Be gentle, I'm still a virgin," my mom mewed, and wiggled against the head of the fake cock.
"I'm going to give it to you rough as I want. I'm going to fuck your virgin puss so hard you're going to cry, bitch." With that Aunt Linda thrust her hips forward and slammed the dildo into my mom's pussy. Mom barely cut off a scream of pain and delight.
"Please don't hurt me," Mom begged. "I won't tell anyone you put your dirty cock in me, just don't hurt my soft pussy."
"Shut up, slut. This is my pussy, understand? And I'll fuck it any way I want." She pulled back and slammed into her sister again. Mom grunted with pleasure. My aunt then began riding her with a slow, steady rhythm. The movement sent my mom's pendulous breasts swaying forward and back in such a way that my balls tightened with desperate yearning.
"It's too big," Mom whined. "Your cock is too big for my little pussy."
Aunt Linda raised her hand and brought it down hard onto her sister's rear end. Smack!
"Ooo!" Mom squealed. "Please don't spank me, I'll be good." SMACK! Aunt Linda delivered and even harder slap to her other cheek.
"I said shut up, bitch!" My aunt picked up her pace, humping my mom harder and faster. Mom's hanging boobs began to swing and flap together. I was feeling like a caged dog left to starve with a pile of fresh meat just beyond reach. I noticed Aunt Linda looking toward my hiding place. She grabbed onto my mom's hips so she could get more leverage on her thrusts, and blew me a kiss.
The door swung open and before I was consciously aware of what I was doing, I had stepped into the room. My mom's eyes widened when she saw me standing there naked and ready for action.
"No," she moaned, "don't look, sweetie. I don't want you to see me like this." Even as she spoke, my mom continued to match the thrusts of her sister's dildo.
"It's okay, Mom," I said as I moved closer. "I know all about what you and Aunt Linda do together."
"I don't want anyone to know that I lick my sister's pussy." She caught one of her wobbling tits and fondled it as she watched my hard cock get closer. "No one knows that I let her put her fingers and her tongue in my cunny."
"I know, Mom. One day I'll know all your dirty secrets. If you let me." I took one more step and was finally close enough for Mom to take me into her mouth. She did so with manic urgency.
The deluge of sensations assailing my brain was overwhelming. My mom's mouth closed around my cock like a velvet vice. She sucked me hard as the natural motion of her sister fucking her from behind propelled her down and back on my aching shaft. Added to that was the visual feast of my aunt humping my mother, her bare tits bouncing in time to her plunging thrusts. I reached around either side of my mother's torso and took hold of her dangling breasts and that was all it took to put me over.
I convulsed and cried out as I unleashed my first orgasm of the night almost immediately into my mom's mouth.
"That's it, boy, fill that slut's mouth with your cum." Aunt Linda administered another slap to her sister's ass. "Make her eat your filthy spew."