After receiving the 'aphrodisiac pills' from her students, Mrs Watson went where her husband relaxed sitting in a beach chair watching the movement on the beach. "Hello, dear." she said, informing him of her presence as she tucked the pills into her bag.
"Are you back from your walk on the beach, Karen? So how was your walk?" her husband (Nate) asked
"It was great, I even met some acquaintances who gave me a 'little gift'. With that I was wondering if you would like an intimate moment just between the two of us?" Karen said sitting on her husband's lap, allowing him to feel the weight of her balls in his lap as well.
"Karen, you know I'm not interested in this. You're tired of knowing that I think your high libido is your biggest flaw, which is why I think you're better off being invisible, so I don't need to see you every time you touch yourself and even masturbate at home." Nate said
"I know you're not interested in sex, but I've been given a wonderful aphrodisiac pill that might solve this problem. I know you don't like it, but could you take one of these pills to please me and have sex with me only this once?" Karen said
"If it's just once, I'll accept it, but let's go somewhere more reserved. You may be invisible, but I am not. What would people think if they saw me having sex with air?" Nate said
Mrs Watson agreed with her husband, so they packed up and went to their hotel room. On the way, she took one of the pills with the intention of preparing herself, thereby undergoing a transformation that no one saw or noticed, including herself, thanks to her invisibility and alteration in reality.
Once they entered their room Karen became visible (as she had gained the ability to switch to be visible or invisible whenever she wanted) thus showing her new body. She now had three legs side by side, with two crotchs each of which had its own 6 foot long horse-cock and balls. Her body was also entirely covered in scales, as were the lizard tails that stretched over the now chameleon woman's two asses.
"You can give me this aphrodisiac you said you have now." Nate said and Karen, very excited, took a pill from her purse and handed it to her husband, who took it.
A few seconds after Nate swallowed the pill he transformed, his legs fused and stretched into a long snake's tail as his clothes dissolved and disappeared. Two pairs of breasts grew on his chest at the same time a second pair of arms emerged below the originals, his/her neck stretched before splitting, leaving Nate, who now answered for Nadia, with 8 heads in his/her long necks, just like a hydra. Finally, her balls were sucked into her body, leaving a vagina in place, while her cock remained temporarily intact in place of her clit. Her new vagina split in two along with her dick, eventually each of her two dicks split into four and stretched until each was ten feet long. In the end Mrs Watson's husband had become a mix of lamia and hydra, having a female body with 4 arms and breasts, 8 heads at the end of long necks, a 20 foot snake tail instead of legs, 2 vaginas and 8 sticks that were 10 feet long each, but thin and could be moved freely like tentacles.
"You were right, I have never been this horny before." Nadia said
"Now that you're ready we can get started, can't we?" Karen said and, getting a thumbs up, advanced on her 'husband' with her rock hard horse dicks and immediately shoved them into Nadia's pussies. In response, the lamia/hydra took her cocks to penetrate her wife's pussies and assholes, then guided one more to her mouth and rubbed two of them between her breasts. Nadia then guided her last free cock to fuck her own ass.
It didn't take long for the couple to reach the first of several orgasms they had had, as they continued to fuck each other until they were too tired to continue and fell asleep.