Disciplinary Action/Disciplinary Office/First week/Charity/Bevvy/Skirt only, augment punishment/Love
You definitely want all of her, whether her brother did everything with her or not. You gotta think about how to do it right though. If this were a normal seduction, you might start with kissing. However, you want to get a few "yes" answers out of her first in order to lower her guard, and fortunately for you there is a step much deeper into the process you have actually confirmed her brother did.
"Well then, let's start with what we know." You say, reaching between Charity's legs and softly placing your hand on the crotch of her panties. "Your sister said he touched you here like this, is that true?" You ask her as you begin to gently massage her nether region.
"Uh-huh!" She nods. "Mmm... that... feels good." She says.
"So, you said your brother touched you here, but did it feel this good when he touched you?" You ask her as you continue to massage. She stays silent for a while and just stares at you while you continue to mold and caress her genitals through her underwear. "Did he do this when he touched you down there?" You ask. "Was it soft like I'm doing, did he get his whole hand into it and make you feel good in your privates?" With that, you begin to increase the pressure in certain key areas, grinding her labia in order to maximize her pleasure.
"Mmm..." She moans, but still doesn't respond.
"Do you like how I'm touching you right now Charity?" You ask her. "Even if he didn't do it like this, it doesn't mean I will stop. I will stop though if you don't answer me right now."
"Mmm..." She moaned again and then shook her head in the negative.
"So, this feels better than when your brother rubs you then?"
"Y-yeah." She says breathlessly.
"Alright, so then, I bet he did touch you under your underwear though, he had to if you stuck your classmate's hand into your underwear. Did he do it like this?" You ask, and then slide your fingers around to push the crotch of her panties aside and get your fingers underneath.
"Mmm... sometimes." Charity responds, clearly quite into all of this. You can see out the corner of your eye meanwhile that her little sister is getting rather anxious.
"Bevvy, it's fine if you want to go over and watch from the chair, you can rub yourself while you watch me rub Charity."
The small almost nude girl quietly accepts your offer and takes a seat, bearing her still cum-leaking pussy to you as she slowly rubs it. Meanwhile, Charity has begun to press her groin into your hand, seeking greater pleasure and you grin as you notice she is getting wet. Well, now it's time you figure. One more thing down below first though. You maneuver your hand around inside her panties and manage to find the top of her slit, and the little bump at the top of her prepurse covered clit. "Did he ever touch your little button up here?" You ask.
Charity's breathing has quickened a little as she looks up at you. "Ahh! Umm! A little, but not like that." She says.
"How did he touch it?" You ask.
"On..only a little when he took my underwear off and was looking. He just... uhh... poked it and then he stopped!"
"So, he DID take your underwear off then?" You ask, and then you stop rubbing her and grab the sides of her underwear in order to pull them down her legs. She gives a disappointed whimper.
"When did he do that!?" Bevvy asks. "I didn't ever see!"
"Umm... he only did it in the bathroom and when daddy wasn't home." She said. "Actually, I guess I was the one who pulled them down while he watched." At this point, she seemed to be absolutely shaking with anxiousness as she looked back at you. "Umm... Mr... Mr. Gardner? Is it alright if you do that again?"
Oh, she is really so close to the edge of climax. You can just see it. "Alright." You say, and then start rubbing her now exposed groin once again. "So, does he pull the lips appart and look like this?" You ask, prying appart her labia and gaping open her vagina in the process. You can see inside her now, and you can see no sign of her hymen.
"Mmm... no. He just looks without doing that." She said.
"Ok, then, how about this?" You ask, sticking your thumb inside her vagina. "Has he ever put a finger inside your hole here?"
"Uh-uh." She says, shaking her head.
"Well, did he put anything else into this hole?"
"N..nooo... I don't let him cause it bleeds."
Bleeds? Well, that's an interesting thing for her to say.
"When does it bleed?" You ask.
"Umm... when I put a marker inside, it started bleeding a little, and then in the summer it started bleeding again sometimes and it keeps bleeding. August got really scared when he found out I was bleeding and he hasn't touched my privates at all since then."
So, if you have this right, she broke her own hymen with a marker over the summer, and then coincidentally her periods also started around the same time and she probably seems to think it's because she stuck that marker inside herself.
"Have you ever told anyone except August about you bleeding?" You ask her. She responds by shaking her head.
"Nooo..." She says.
"When was the last time you were bleeding?"
"Umm... I don't know. It was a little before school started."
"And that was the last time August touched you down there?"
"Uh-huh. He said he thought it was caus he kept touching me so he said he wouldn't anymore for a while."
So, if you have this right, Charity must be getting horny because she's ovulating now, combined with the fact she wasn't getting stimulated by her brother anymore. This is what likely lead to her wanting to fool around with that boy during recess, a little bit of a slave to her hormones. She is quite likely at the absolute height of her fertility right now, a nearly guranteed chance of getting pregnant if you were to fill her up right now. You have already dumped two loads into her sister today, but the realization of what's going on here has you getting stiff very fast.