fun with sis and friends

it all started one day when i was watching a movie in my room while my sister and her ttwo best friends were having a slumber party.i was 17 at the time and still a virgin. my sister,amanda was 13. her two friends mackenzie and rachel were also 13 with nice sized boobs for 13 year olds. it was about 11 pm and as i started to fall asleep i heard some moaning comming from the room next to mine. of course we were the only ones in the house for the weekend. our parents had gone to a business conference out of state. as i walked toward my sisters door the moaning got louder and louder. i figured they were just watching a porno they found in my parents room. when i reached the door i looked in a little and saw that my sister was laying on her back on her bed with her beautiful 36C boobs sticking up in the air.(i know the size cause ive looked at her bra few times cause i was curious.) i openned the door a little more to see who was making her moan like this. it was her best friend for the last 10 years mackenzie. i would have to say she has 34C boobs. she was about 5’4″ 85 pounds. as my sister screamed to mackenzie licking and sucking her pussy i saw rachel with one of her 32D boobs in her hand and her other hand down her pants. since i was horny i decided to jerk off right there watching the three of them playing with each other. as i neared blowing my load i let out a cough and they stopped suddenly.
as i stood there with my cock in my hand they cleaned up and oppened the door with me right there. i tried to get it back into my shorts i just couldnt do it. as the three of them looked at my cock, mackenzie asked me “what is that in your hands” as amanda and rachel giggled
all i could say was that it is a penis. the three of them just looked at each other to see if any of them knew what it was for. after a minute or two i asked them ” is this the first time you’ve seen one of these” and they all nodded yes. i asked them if they had any idea what its for. rachel said that her older sister told her its how boys go to the bathroom and its for girls to play with during sex.
after a few minutes i asked them if they wanted to touch it. amanda and mackenzie said they would only if rachel did first. rachel agreed. as she put her hand on my cock, i felt a shiver go up my spine. when she let go amanda and mackenzie kept their word and touched it. amanda went last as she touched it she loved the way it felt and didnt want to let go. after she let go they started asking me some questions about sex cause their parents hadnt talked to them about it yet.
first rachel asked me why girls touch a mans penis.