Isabelle grinned as she felt her womb absorb all her sister's cum, putting it to good work changing her body for the better. Of course, one load wouldn't fully turn her - she knew that for a fact - but with the size of her load, her changes would still be impressive.
The first thing she noticed was her legs were getting longer. Not her whole body, just her legs, extending and adding a good half a foot to her 5'4 height. With the extra muscle she'd packed on, they were definitely still strong; and toned, too. Perhaps, with a few more shots of cum in her pussy, they might have fused and become a snake's tail. As it was, they were just extremely long and sexy legs that highlighted her figure spectacularly.
Her legs weren't the only thing to grow, though. Her neck was soon to follow. It stretched higher and higher, a full foot in length, then two. Her still-human head waved around on a long, fleshy tentacle of a neck. She found that she could make those darting movements quite hypnotic if she wanted, no doubt thanks to the cum she'd received in her ass. Her tongue flickered out, long and black and forked, like a snake's. She hissed in delight, before another change began.
This one was far more strange. She could feel her face widening, and then suddenly she could see further as two more eyes appeared, then four. They all pulled apart, stretching her skin further and further, until POP! suddenly she could see from three different angles. She turned to look at herself.
"Wow," said one head.
"Freaky," said another.
"Cool!" all three chorused at once. As she felt the changes finish and all that cum finally disappear within her, Isabelle slid herself off her sister's cocks. Melody was still half-cohesive, spent from being milked dry by her sister's body, and she began to protest as the nympho sashayed away to find her next meal. A quick, hypnotic kiss from Isabelle quickly shut her up, though, leaving the wolf anthro reeling on the floor.
Isabelle's eyes narrowed in on the prize, the two busty giants that lay groaning on the bed. She licked all three of her lips. She was about to pounce, when Max stepped in front of her, and clicked his fingers. Instantly, she went limp, and her eyes showed spirals.
"Now, just a minute," Max said, holding up a hand. "First things first..."