James jumped up, wiping his mother's ejaculate from his chest. Margaret was right as far as James was concerned. The three of them had to get to Margaret's lab to look into what was causing their changes. As James grabbed his things and returned to the family living room, he was taken aback at the changes to his family.
Margaret had bulked up considerably since her second orgasm. The mother's slim figure was gone. Now, James could see muscles straining against Margaret's formerly loose fitting jeans. Her blouse was also straining due to new chest and arm muscles that had developed. Fortunately, from breasts on up, James' mother seemed to be the same woman he had always known.
Turning his attention to Sam, he was relieved to see his sister had not developed too many changes of her own. While her hair did have somewhat of a wild, feral look, the rest of Sam's features remained mostly the same. As with her mother, Sam's new cock had drooped down the side of her pant leg.
Seeing James getting ready to leave snapped Margaret and Sam back to the present. The two quickly joined James in heading out to the car and to Margaret's lab. Not long into the drive, James was distracted by a slight moan from his mother. Looking down at Margaret's jeans, James could see that the vibrations generated by his car were turning his mother on. Meeting Sam's eyes, James pulled over and stopped the car and waited for his mother's penis to return to a flaccid state. The rest of the drive was slow going, with James having to stop several times to let his mother's lust subside. Eventually the trio arrived at the lab.
"Thank god we're finally here", Margaret exclaimed. "I wasn't sure how long I could hold out. I know it was slow going, but still." the mother finished as she gestured to her new penis.
"You're not the only one thankful to be out of that car mom." Sam agreed.
"We're not out of this yet, lets get to the lab." James reinforced.
The three were greeted by one of Margaret's assistants as they entered her lab.
"Hey Margaret, you weren't planning to be in today were you? Something come up? Have you been working out?" the assistant asked in a flurry of questions.
"Yes, just a bit of an issue. Ben, can you run some diagnostics on this fluid for me? I just need to know the makeup of it for further analysis." Margaret responded. The woman stood awkwardly, doing her best to hide her new penis.
"Of course!" Ben exclaimed, as he took the cum sample jar from Margaret. She turned back to her children with a tired smile and was about to begin going over her plan of action before she was interrupted by a crash from behind her.
Unbeknownst to the three family members, the spirit had joined them in their flight to the lab. It saw the college and lab as a perfect opportunity to create more chaos, with Ben providing the perfect first target. The spirit's effect on Ben caused him to stumbled and knock over some vials.
"My mistake everyone. Sorry for that." Ben muttered apologizing.
"Oh, don't worry about it Ben. We can clean it up in a moment."
As Ben opened the jar to test its contents, he was taken aback at the odd smell emanating from it. "Wow, that smell's really good" Ben thought to himself. Shaking the thoughts off, the assistant proceeded to test the jar's contents. After another couple sniffs, Ben absently reached into the jar and took a taste of its contents. The lab assistant's mind eventually settled into a haze as he took a second and third taste of the cum. This haze distracted Ben from his ongoing changes.
Considerable breasts had begun to grow in on the man's chest. As the breasts finished settling in, nipples extended outwards creating small tents in Ben's shirt. Small milk droplets began forming at the end of the nipples. Most dangerous to the room's inhabitants, however, was the scent that Ben began to expel.
James was the first to notice the effects of the scent. "Hey mom, are you okay? Your thing looks to be growing a bit."
Margaret looked down in surprise at her stiffening penis. "Now that you mention it, I do feel a bit strange. I don't see what could be causing this though."
"I'm starting to feel weird too." Sam agreed. Sure enough her new addition was slowly extended into her panty and crotch area as well.
"Hey Ben, did you turn the AC off or something? There's a weird smell in the air." Margaret asked. Not getting a response, the woman went over and asked the man again. "Earth to Ben, do you smell anything weird?" Margaret was cutoff as Ben turned around.
The man's hands were thrust into his pants as he jerked his cock wildly. Streams of milk could be seen dribbling down Ben's chest as he continued his motions. The sight of his attractive boss sent James over the edge. "Oh Margaret, you're so beauti-OH" the man was cut off as he ejaculated into his pants.
The scene of her assistant's orgasm froze Margaret. James watched as the previously small bulge in his mother's jeans rocketed out. Margaret, for her part, tried to fight her hormones before succumbing. "Ben, what happened to you? Why is... Oh, I don't care. I horny. I need fuck. Please suck me. Oh god."
Margaret's clothing seemed to continue to tighten as she gazed lustfully at Ben. The mother slowly began rubbing her rock hard cock, desperately wanting to pleasure it to orgasm. Eventually, enough was enough. "I not care. I need release. It not matter how."
James watched in a daze as his mother thrust herself at Ben, knocking him over. The mother positioned her cock between Ben's new breasts and began thrusting mindlessly. "Oh, so good, so good. OH YES!" As soon as it had begun, it was over. Margaret shook as she expelled her cum from her cock. Silence filled the building outside of a rubbing sound.
James turned to his sister who was also under the control of the scent in the air. Sam's expression and hair had taken on a wild look as she jacked her cock off in her jeans. "Oh mom, that was so hot." Sam mumbled. "Do me next. Do me-UGH" the girl grunted as she ejaculated herself.
James sat back to watch in horror as the next changes took place.