Denise awoke the bright light shining down into her room and yawning she sat up the blanket falling from her body. As she looked down she grimaced at the flat chest she had, groaning she got up and walked out of bed dressed only in her panties. She opened the door to her room and walked out she headed to the bathroom to freshen up. The door was closed but it was soon opened and the nude, steaming, and wet form of her sister Mary came out. Denise glared at her older sister, unlike her Mary was blessed with a prodigious bust, a 37 G cup she had started getting it early in life around middle school and he bust grew at an exponential rate. By the time she was in high school she had to get a DD cup bra and soon became not only eye candy but the most desired girl in the school. Mary though was resolute in not having a boyfriend at that early age. Instead of deterring boys it made her even more wanted. Mary however graduated and left many boys with broken hearts, Denise went to the same high school that Mary had but never garnered the attention and lust of the boys that her sister had.
Ever since Denise left high school she had she had a deep hatred and jealousy for her sister. Especially considering her sister was the only one with that bust no one else in her family ancestry had it. Denise had often had suspicions that Mary’s bust was augmented but every time she felt them they felt completely natural. What she had noticed though was that the breasts were heavy and when squeezed she would produce milk. Which Denise found odd considering Mary never had sex or children. Denise walked into the bathroom past her sister and closed the door to wash.
-A few Minutes later-
As Denise walked out of the bathroom she walked to the stairs and was walking down it toweling her hair and looking at the dining room she stopped. Mary was standing and was leaning over a bowl the family cat Nina meowing up at her. Mary straightened up and the bowl was filled with milk. Denise watched as she put the bowl on the ground and Nina began to lick up the milk. Mary giggled and she walked to the living room and sitting at the couch and turning on the TV she drifted off. Denise walked downstairs and looked at the cat, the cat was happy enough licking up the milk. As she watched the cat licked it’s chops then began to walk away raising its legs slightly higher as if having to deal with an added load. Denise grabbed the cat and lifting it up she looked to see what the problem was. Her eyes widened as the cat’s lower breasts were larger than before. Denise put the cat down as it mewled in protest and she looked at her sister shocked then a thought occurred to her. She smirked and going upstairs she began to make plans.
-1 hour later-
Mary inhaled deeply making her breasts push out then she exhaled her hands lowering. She watched the woman on the TV carefully. Mary was a fitness freak and had several DVD’s on workouts and had a channel favorite that did many different work outs for the day or week. Right now they were doing breathing and meditation exercise to help clear the mind and body. Despite the seemingly effortless task it was very exhausting **77** your body to a certain state of stillness and your mind to ignore the aching. “All right and now we’ll do a 15 minute cool down! Get your energy ready for some more work we’ll be doing some leg lifts…” as the woman droned on Mary sighed and stood her muscles sore. She went to the kitchen to get something to see Denise standing there pouring lemonade into a glass.
“Oh… hey Denise!” Mary said, Denise turned her head.
“Hey,” She said monotone and went back to the glass. Mary looked at her sister expecting something but nothing happened. “Thirsty?” Denise suddenly asked.
“Oh yeah that stuff always makes me thirsty!” Mary said, Denise handed the glass she had poured to Mary and Mary took it and drank deeply drips of cold water going down her chin and between her massive cleavage Denise looked at the drop bitterly. In her mind though she smiled slyly and she headed up the stairs to her room. Mary drank the lemonade and removing it from her lips she gave a great gasp of relief. She looked for Denise and saw her coming downstairs wearing a red button shirt and jean short-shorts. “Where you going?” Mary asked.
“To the basement I gotta look for something I’ll be up in a bit it’s cold down there you know.” Denise said.
“Oh… okay…” Mary said glumly, Denise headed to the living room then walked to a small opening which lead to a stairs that were inside the stairs up. She opened the door and walking inside she vanished, Mary sighed and went back to the TV there were still ten minutes left before the workout started again. She sat down and crossing her legs she began to do the breathing and concentration exercise to help prepare herself. She sat there and closing her eyes she began to concentrate and as she did she found her mind to be drifting. Her body was heavy, heavier than before and her eye lids shook as she tried to resist the temptation to fall asleep which was in her so strongly now. She started to drift and then she **87**.
-An unknown amount of time later, in the basement-
Mary groaned her body heavy especially her chest which felt like it was being weighed down by a massive weight. She opened her eyes and she gave a muffled scream, the gag ball vibrating, as she saw that her breasts were enormous at least the size of a small boulder! She then heard footsteps and she tried to turn but realized she was tied to a pole and was also bound via her hands and feet. The person came to view it was Denise a smug look on her face. “Hello Mary, surprised? It’s a little something I did… actually rather something you did to yourself.” Denise said, as she walked around she placed a nail on Mary’s breast and drew it down digging in to mark the skin with a red mark. Mary moaned slightly the stimulation of her over-sized breasts exciting her forcefully. Denise removed her finger but the burn of the scratch was still working on Mary.
“You know it’s rather odd how you manage to get such big breasts while everybody else in our family was flat. I’m rather curious as to how it happened…” Denise said and walking up to Mary she pulled the gag and let it fall. Mary panted and looked at Denise tears in her eyes.
“I-I don’t know!” Mary said, Denise waved a finger and smacked Mary.
“Stop lying! I know you did something it started when you were in middle school! Now what did you do?” Denise shouted.
“I don’t I just started growing like that and… and well…” Mary said trying to think, “Um… I don’t know!” Mary said.
“Well then… since you seem to be incapable of remembering I’m going to have a bit of fun…” Denise said, Mary opened her mouth but Denise used that to stuff the gag back on. Walking to Mary’s breasts Denise got to her knees and placing a hand on her breast she pushed. Mary moaned as her nipple began to spray small gushes of milk. Denise then wrapped her lips around the nipple and began to suckle. Mary moaned as her sister sucked her breast milk gulping it down loudly. After twenty seconds Denise pulled away and looking down she saw her bust had increased to a C cup. “Oh god yes I finally have boobs!!” She grabbed her new breasts and hefted them feeling the new weight and the sensitivity. “This isn’t enough I need more!” And Denise once again began to suck the nipple harder this time and even pulling slightly to increase the flow. Each gulp made her bust grow, her top popping up as she drank and after two minutes of suckling Denise released the nipple and gazed at her new E cup breasts with glee. She grabbed them and began to play with them cooing at the soft flesh. Her body shuddering as she turned herself on. “Oh godddddd… this feels so good and hot…” Denise said.
As she played with herself her crotch moistened as she began to sweat and her breath was heavy with lust. She lowered one hand and began to play with her pussy moaning slightly her eyes closed her body squirming from the sensations she was nearing orgasm but she stopped and looking at her sister who was watching her closely she smiled and standing up she walked to a wall where there was a chest and opening the chest she rummaged inside and she pulled out two dildos, a large black dildo easily a foot in length and as thick as a man’s arm and a pink one about 9 inches in length and 4 inches in thickness. Mary’s eyes widened in horror and she shook her head rapidly. “You know something sister we have some catching up to do… A looooooooooooot of catching up!” Denise said walking toward her sister he moaned softly…
Ok this took longer than I would of liked but hey it's done! Enjoy!