The affair between Julie Jenkinson and her now eighteen-year-old son Christopher was not abating and they were having sex,on average, three times a day.

Julie had purchased a cane as one of Christopher's eighteenth birthday presents and he now felt that across his arse more frequently than his mothers hairbrush with him usually wearing female clothing when the beatings were administered although they had long ceased to be punishments as both parties got pleasure from them.

For a change Julie was about to have her son,dressed in a short skirt and a blouse, over her knee for a bare arsed hairbrush spanking but before the spanking had finished they were unexpectedly to be joined by a third party.

Nineteen and now almost twenty-year-old Catherine had initially moved out of the family home to share a flat with a female work colleague but had since moved to a flat of her own in another town. She had decided to pay a surprise visit to her mother and brother although they would not be the only ones surprised because she had no idea about Christopher's crossdressing or his passionate affair with their mother.

It had been Catherine's old school uniform that had led to what was now happening because Julie caught her son wearing it and gave him a good hiding, things very much escalated from there.

CRACK! CRACK! CRACK! CRACK! CRACK! CRACK!

Julie,seated on a kitchen chair, had commenced the spanking of Christopher's bare backside and neither she nor her son heard the front door being opened by the key that Catherine still possessed.

CRACK! CRACK! CRACK! CRACK! CRACK! CRACK!

Catherine was by now looking open mouthed at her mother spanking her brother whilst the boy was dressed as a female.

CRACK! CRACK!

The hairbrush was raised once more when Catherine at last announced her arrival by saying, "What the fuck is going on?"

The hairbrushes descent was halted as both Julie and Christopher looked up in shock, "Catherine, wwwhat are you doing here?" stammered Julie.

Catherine ignored her mother but exclaimed, "He is fucking wearing girls clothes!"

"Go upstairs Christopher, I need to talk to your sister," Julie advised her son.

As Christopher got off his mothers lap Catherine let out another pronouncement, "He's got a fucking hard on."

Julie spent the best part of the next two hours pacifying her daughter and explaining what had been going on in her absence and during that time the young woman heard that her brother had worn her old school uniform, had been soundly spanked,had worn his mothers clothes, again got spanked and now mother and son shared a bed.

It was a hell of a lot for her to take in and at the end of it she said that she had only come to see them to give them a surprise and that she hoped to be able to spend the night in her old bedroom.

Julie managed to convince her daughter to stay the night but was concerned that she had to go to work because the shift that evening was unavoidable, "Will you be okay being here with Chris?" asked Julie.

Catherine laughed, "He is only a pervert, not a mass murderer," and then realised that what her mother was doing would be seen as perversion by many.

Christopher had not been heard from since going upstairs shortly after his sisters arrival and shortly after Julie had left for work Catherine decided that she would go and see if he was okay.

She knew that he now shared his mothers bedroom but when Catherine looked in there it was empty but the door to what was her brothers room was closed.

She knocked gently on the door. "Chris,are you okay? Can I come in?"

There was no audible response but she decided to go in anyway.

She was slightly surprised to see him dressed in his own, male, clothing.

"Hey! seems things have changed a bit since I moved out," she said smiling weakly.

Christopher did not speak but Catherine continued, "Mum told me everything,about my school uniform, about you and her..."

Still Christopher said nothing but what Catherine said next jolted him a bit, "Mum said you looked hot in my uniform."

Christopher spoke for the first time, "Did she? How would she know,she was tanning my arse at the time."

"Well I suppose she has thought about it a lot since," replied his sister.

Christopher just grunted in reply but then Catherine said something that surprised even herself, "Chris, will you let me see you in my school uniform?"
 

"Fuck off, no way," he responded.
 

"Please, I want to see if I think you look hot."

"No, you are taking the piss."

"I am not, I really want to see you in it."

It took a bit more convincing but soon brother and sister were in her old room and Chris had started to remove his male clothes.
 

He was down to his underpants, which were bulging at the front, and Catherine said, "All of it, you have to wear my old school knickers."

Chris turned his back on his sister as he removed his underpants so she saw his buttocks with the red marks from the earlier spanking.

He put on the uniform and turned to face her, "Wow, you do look fucking hot!"

Catherine had not really noticed before but she now realised how wet she was between her legs.

"Do I really look hot?" asked Chris.

"Fuck yes, look how wet you have made me," said Catherine spreading her legs so that her brother could see her damp white knickers under her skirt.

Catherine's eyes then went to the bottle green knickers that her brother was wearing and how they were stretched at the front under the short school skirt.

It was as though somebody else was saying  it but Catherine heard coming from her mouth, "Chris, you have got to fuck me."

"No, Christ no, Cathy."

"Why not, you are fucking our mum?"

"But, but..."

By now Catherine had taken off her wet knickers and her glistening cunt was exposed as she lay back on the bed.

Christopher's prick was throbbing and he thought to himself that there was no difference between shagging his mum and his sister.

Catherine had moved further back on the bed and her wide open cunt was begging for his cock so he swiftly removed the green knickers he was wearing and approached his highly aroused sister.

She guided him into her and they slammed against each other, "Fuck Chris you are big, no wonder mum is so happy."

They were both approaching a climax and she came first, "Shittt, oh fucking hell,oh..."

A few more thrusts and Christopher shot his spunk into his sister.

They lay in joy and in shock and thought of the implications of what they had just done.

When Julie came home from work she was not entirely surprised by what she found when she set her eyes on her daughter and son cuddling on the settee with him being in his sisters old school uniform.It was quite obvious that neither of them were wearing underwear.

These days Julie seemed to take every new discovery in her stride. "So what have you two been up to, as if it wasn't obvious?"

"Mum, can Chris sleep with me tonight please?" asked Catherine.

"I suppose so, it is only for the one night after all."

An hour or so later Julie was bringing herself off with her vibrator as in the next room, as the bed creaked, her daughter shrieked, "Fuck, I am cumming again."

The dynamics in the Jenkinson family had taken another twist.