It was twenty minutes before Isabelle arrived, clearly indicating she had not been at all ready for her early summons. I had spent that time carefully considering my strategy. Isabelle increasingly seemed to be pushing back about the discipline and regime that I was attempting to enforce, to the extent that I now thought she was deliberately behaving poorly in order to gain more severe punishments. She would then endure the punishments I sentenced her to almost as another form of defiance, showing me should could take them but that they didn't have any effect on her behaviour. It had been particularly hard on Isabelle to have lost her real mother at the young age that she did and she had found my coming into her family's life difficult to adjust to, but I had concluded that if I didn't take decisive action now, it might be too late.
Isabelle had knocked on the door when she arrived and I now called her into the study. I was disappointed with her attitude from the start. She flounced in and just pushed the door shut behind her with a noticeable bang rather than closing it politely as her elder sister had done. She stomped to position in front of the desk and almost threw her hands on top of her head before sighing audibly. There was no pride in her pose - her elbows and shoulders weren't in line and her left leg was bent slightly giving her a lopsided, lazy look. There was no denying she was Rachel's sister as the two of them looked very similar. Isabelle was a little taller and had a slightly more petite frame. But with a bra size to rival her sister's her bust was easily as noticeable and Isabelle liked to show off her longer legs whenever she could. That was just as well as although Isabelle's uniform was very similar to Rachel's, I had insisted Isabelle wore a much tighter, straight black skirt which clung to her buttocks and finished just below them. Isabelle had naturally darker hair than Rachel as well which she wore in face framing layers which reached just past her shoulders.
I looked up at her from my seat behind the desk and waited patiently. After several seconds she sighed dramatically and adjusted her pose so it was of a standard I would expect. Only then did I begin to speak to her.
"It's been a difficult week for you Isabelle, hasn't it?" I queried. Everyone else called her Izzy, but I always used her full name - it was more formal.
When Isabelle didn't answer, I continued. I looked down at the behaviour ledger I had placed on the desk before Isabelle entered to ensure that I got the details correct, but this was really just for effect as I was already very clear.
"On Monday your college rang to say they had some concerns about your progress in some of your subjects," I reminded Isabelle, "and that was largely down to a lack of effort on your part."
Isabelle again remained silent so I moved on to the next infraction. "On Wednesday you took the wrong leotard to gymnastics which led to the whole team losing points."
Isabelle shifted slightly at being reminded of that. I believed that had been a genuine mistake rather than an act of defiance, but it was still something that needed correcting again as part of Sunday discipline.
"And on Friday you got home late and were dressed somewhat inappropriately."
I sat back in my chair, folded my arms in front of me and looked directly at her. Of course she had been punished for each of these things during the week but Sunday discipline was a time for reflection on the week as a whole.
"What have you got to say for yourself, Isabelle?" I asked.
Even though I was used to Isabelle's rebellious nature by now, I did still expect some sign of contrition or a simple apology but Isabelle had clearly decided to double down on her obstinate behaviour which she had displayed throughout the week.
"Can we just get my discipline started?" was her response.
I nodded slowly, resigned to what I would have to do, but reluctant to do it all the same. That chance for her to explain or apologise had been the last chance I was willing to give her to show she was at least going to try to improve her manners and behaviour.
"Isabelle," I said seriously, "I am afraid I am going to have to advance your discipline to level 4 as level 3 techniques are just not working for you anymore like they do for your sister."
"Oh what does that involve?" Isabelle fired back smartly. "Chastity belts and butt plugs?"
A little grin played across her lips. I looked down at the book on the desk, allowing her to think she had embarrassed me and giving her that moment when she thought she had scored a point.
But then I lifted my gaze to match hers again and calmly and evenly I replied, "No, prolonged chastity training and anal training are both level 5 techniques."
The play of emotions across her face in the next few moments was intriguing. First she looked disappointed that her explicit mention of disciplinary techniques we had never spoken of before had not shocked me. Then she looked annoyed that my quick retort had completely out-witted her and then, finally, she looked a little fearful as she realised I was telling the truth.
"So four major demerits this week," I clarified, "which is an extra twenty four of the strap on top of your mandatory six."
Isabelle was quite easy to read. She was clearly thinking that this was going to be tough but that she had taken worse before.
"But Level 4 Discipline is not just administered across the buttocks, Isabelle," I explained. "I think you are going to find this very difficult but remember I want the very best for you which is why I put the time and effort into making you the best young woman you can be."
I could see Isabelle was nervous. All discipline I had administered to both girls so far ever since I had begun had been focused on their bottoms and, naturally, over time both sisters had developed a certain resilience as well as a knowledge of what to expect and strategies to help cope. With the prospect of unknown discipline about to be administered, Isabelle had lost some of her sassy, confident attitude.
"Strip down ready for discipline, please," I instructed her, "you can still keep your regulation knickers in place."
That reminded Isabelle that if I was being particularly harsh I could make her strip naked.
With obvious reluctance Isabelle got to work unbuttoning her blouse. She shook it from her shoulders, making her breasts sway obviously as she did so and when the garment fell to the floor she left it there in a crumpled pile. She took her skirt off next which took more effort than Rachel's had. Isabelle's was so tight across her bottom and thighs she had to force it down to her ankles before stepping out of it. She faced me insolently to remove her bra and once it was off she dropped it to the floor and resumed her attention pose.
"There," she announced when she was stood before me in just her white regulation underwear and her shoes and socks, "happy now?"
