I don't own the Loud House.

Welcome back to another chapter. I'm sorry for the slow updates, I have familial commitments during the holidays and it makes it hard to write. I'll try to post a new chapter every two weeks as that schedule seems more manageable. If you want to know for sure, I post regular updates on my twitter.

We're nearing the end of the Luan arc and afterwards, we're going to move onto Luna and Lynn. I have some interesting plans for both and they'll be happening at the same time, kind of. You'll see what I mean once I start on them. Also, Lori has been busy during the week that she gave Lincoln and Lisa and we'll be learning what she did as well. Hopefully you will all enjoy it.

What She Didn't Know

Chapter 20

"So what happened after Aunt Leni offered to help you?" Loan asked her father.

"Lori had forbidden me from having sex with Leni until after Luan had been completely broken." Lincoln said with a sigh. "So Leni and I had to find other ways to enjoy ourselves."

Leni giggled as she leaned back against Lincoln's penis. Lincoln was sitting on her bed, lying flat against the mattress without his pants. His hardened member standing tall in the air, just waiting for Leni's attention. And Leni was only too happy to give it to him. She pushed her butt against his dick, enjoying the feeling of his heat against her skin. Leni then looked over her shoulder as she reached with her hand and pushed Lincoln's dick in between her cheeks.

Lincoln groaned as he felt Leni begin to clench her butt cheeks together, his penis being engulfed by her ass. Leni didn't have the biggest butt, Lori's was bigger if only slightly, but what she did have was enough to almost swallow his dick. They had been practicing this for the past couple of weeks since they began to fool around. Since Lori said that they couldn't have sex using Leni's pussy yet, Lincoln had been exploring other ways to have fun with Leni. And this method was one that Leni also enjoyed.

"Oh god, Leni…that feels good." Lincoln moaned as he laid back on the bed.

Leni felt pleased with herself. "I'm going to totes make it feel even better now, Linky."

And then Leni began to move her hips up and down, sliding his dick in between her cheeks like a hotdog through the buns. All the while Leni kept clenching and unclenching her butt, squeezing his penis in the way that she knew he liked. His sounds of pleasure helped motivate her to keep going and soon Leni found herself feeling his precum ooze out of his penis. It helped lube her butt and make it easier to continue to slide his penis in between her cheeks.

"D-Does that actually work?" Loan couldn't help but ask, sporting a rosy blush of embarrassment.

"Of course, my child." Her mother answered at once. "I've performed the act for your father numerous times."

"As have I." Lisa added.

Lincoln looked embarrassed. "I um…like it."

"Apparently." Loan said as she eyed her mom and aunt.

As Leni continued to please her little brother, her own arousal began to rise as well. Lori and Lincoln had explained to her that what she was feeling was called being horny. And whenever she helped her brother out with his boy problems, Leni always ended up feeling horny. And as such, she reached down with her right hand and began to play with her pussy just like Lori had taught her. It always made her feel even better when she played with herself.

"Oh god…Leni…I'm gonna cum." Lincoln moaned. He had already began to slowly buck his hips along with her own rhythm.

"D-Do you…want to finish on my back?" Leni asked him. Whenever he was close, Lincoln sometimes liked to finish on different parts of her.

"Yes!" Lincoln said quickly.

Leni nodded before pulling away from him. She quickly laid down on her stomach on her bed and then waited as Lincoln straddled her. She felt him sit just below her butt and then he pressed his hard dick against her cheeks. Gripping her buns, he spread them open just enough to slide into them before he pressed them back together. Lincoln then began to buck his hips against her butt and made sure to keep his penis inside. Leni moaned as she felt his hot member slide in and out of her butt cheeks, it was amazing just how hot it made her body feel. She was gripping her bed covers as she tried to brace herself.

And then she felt him tense up as he pushed his hips against her and called out her name. A moment later, she felt his hot seed spill onto the small of her back as it shot out from in between her butt cheeks. Leni shuddered as she felt herself reach her own climax. The feeling of her brother's bucking and the burning sensation of his hot boy juice on his back more than enough to help her reach her own orgasm.

They stayed like that for several moments before Lincoln reached down and slid his finger up her slit. Leni shuddered as she felt him begin to tease her pussy. "Linky…Lori said no…" She reminded him with a weak whimper. They both wanted to do the deed but neither wanted to upset their sister.

"I know…" Lincoln said. He moved his finger up towards her butt and then an idea struck him. It was something that he had only done with Lucy so far and technically, Lori never said that they couldn't use the back door. "But what if we didn't use your pussy?"

"What do you mea-eeeeen!" Leni had begun but then her voice carried on as she felt him slide his finger into her butt. She quickly turned around to face him, her face blushing furiously as she tried to stammer out a response. But all she could do was look at him as he grinned at her mischievously. Finally she managed to say. "B-But I poop from there!"

"Not right now you don't." Lincoln said as he began to move his finger. Unlike with Lucy, Lincoln wasn't trying to punish Leni. He was just frustrated that he hadn't been able to have sex with her yet. Sure, they had done plenty of other stuff but Lincoln wanted to take her virginity and make her his just like he had done with Lucy and Luan.

One finger became two and soon Leni was biting her lower lip and was trying to not moan with pleasure. It was obvious to Lincoln that she was enjoying the feeling but didn't want to admit it. Pulling out, he scooped up the semen that was still lying on Leni's back and rubbed it all over her anus. Then he reinserted his two fingers and moments later slid another inside. Leni was no longer looking at him as she had pulled her pillow towards her and had buried her face in it. She was trying to mask her moans and Lincoln knew that she was ready.

He removed his fingers from her anus, leaving it slightly spread open. He positioned his already hard dick against the entrance of her back door and pushed slowly. Leni jumped when she felt him begin to push inside. Her whole body tensed up and Lincoln stopped what he was doing.

"Leni, you need to relax. Otherwise this will hurt." He told her.

"I-I'll try…" Leni said in a low voice. She took several deep breaths and Lincoln could tell that she was trying.

Deciding to help her out, Lincoln slid his left arm underneath her and began to rub her clit with his thumb and index finger. He felt Leni tremble beneath him and she soon began to whimper and moan, almost sounding like a small kitten meowing. As he continued to tease her clit, Lincoln felt Leni begin to relax and he was able to begin to push inside of her. He could feel as her anus began to swallow his dick, her muscles clenching down on him as he entered. While not as tight as Lucy had been, Lincoln marveled at how tight Leni's butt was. If he was being honest, doing anally might soon become his favorite way of doing it.

"Did it?" Loan asked her father, curious despite her embarrassment.

"Yes." Lucy and Lisa said at the same time.

Lincoln just shrugged. "Your mom isn't the only one who has their kinks."

"Oh Linky~" Leni moaned, calling out his name in pleasure as she felt him push deeper into her butt. She had never experienced something like this before and she was enjoying it a lot.

"God Leni…you're soooo tight." Lincoln said, own voice coming out in a whisper. He had stopped rubbing Leni's clit and was now holding onto her hips as he continued to push deeper, his dick already halfway inside. He could feel Leni's body tremble and quiver from anticipation and from the sensation of him penetrating her. Her body felt tense yet excited at the same time, both afraid and eager for what was to come.

And as Lincoln finished fully inserting himself into Leni's ass, Lincoln took a moment to just enjoy the feeling of her walls clamping down on his dick. The heat from her butt was intense, even more so than Lucy's had been though he figured that it was due to Leni being older. With each twitch of her body, her butt would clench and unclench around his member. Every couple of seconds, it felt as if her anus was trying to swallow him in even further than he already was. If he stayed like that, he had no doubt that Leni's ass would make him come just by continuing to tighten around him.

But it seemed like Leni had other plans. "Linky…please…" She begged him, her tone desperate but lustful at the same time. "Please…do it…"

With a nod that she could not see, Lincoln began to slowly pull out of her. She gasped and buried her face into her pillow once more. The sensation of his dick pulling out different than it was entering. She whimpered weakly as he stopped with an inch still inside of her, he hadn't pulled out completely. Then he pushed back inside with the same careful pace he used to enter her. He repeated the process a few times before he felt comfortable picking up the pace.

With a grin, Lincoln raised his left hand and brought it down on Leni's cheek. That earned him a surprised squeak from Leni but she didn't ask him to stop. With another spank, Lincoln began to thrust in and out of his older sister's ass, making her moan louder and louder with each drop of his hand. It appeared that Leni liked getting spanked during sex.

"Oh gosh, oh gosh, yes, Linky, spank me again!" Leni cried out as she pushed her butt against him.

Lincoln was only too happy to oblige and he soaked her a little harder than he had before. Leni cried out in pleasure and he was sure that she had just come as he felt her butt clench down even tighter than before. He was nearing his own climax and he wanted to make the most of this rare opportunity.

"I hope you're ready for this, Leni." Lincoln said as he raised her waist higher. He was standing on the bed now in a half crouch. In this new position, he could thrust his dick even deeper than before. And with the added leverage, he would basically be fucking Leni into the mattress. And that's what he did, thrusting downward with everything that he had left in the tank.

Leni had once again buried her face into her pillow, her muffled moans and cries still echoing around the room. Thankfully Lori and Len had also soundproofed their room or else their siblings would have heard them by now. And as Leni came again and again, Lincoln finally reached his limit. He called out her name as he planted his dick as deep as he could, unleashing his load inside of her butt. He felt several thick ropes of cum shoot out of him before he felt the sudden fatigue hit him and he collapsed on top of his sister.

The two of them lay sweaty and panting on the bed, neither wanting to move or disturb the afterglow of their love making. And Lincoln knew that once they finally got to have vaginal sex that it would be even more amazing.

XXXXXX

Loan looked at her father as if she had just noticed something about him. "You know…as weird as mom is, I find this more disturbing." She told him.

"How?" Lincoln asked, his expression a tiny bit embarrassed and shocked. "You haven't even heard of the other stuff that your mom is into!"

"Hey, we're not discussing my kinks at the moment." Lucy interjected. "Now please continue, baby."

"Well…it's just like aunt Leni said, she poops from there." Loan began. She looked umcortable, if the matching embarrassed blush was anything to go by. "H-How could you stick your…you know, in there?"

Lincoln sighed, closing his eyes for a moment to collect himself. "Loan, it's kind of hard to explain unless you've already done it." Lincoln began. "But suffice to say that it just feels really good. Plus, you can't get pregnant from anal."

"It was amazing that you hadn't managed to impregnate Luan or Luna when you had sex with them in those early days." Lisa remarked as she took a sip of her coffee. "Lori had used condoms and was on birth control but you hadn't used either on the others."

"Wait, speaking of Aunt Luna, wasn't she into Aunt Sam at the time?" Loan asked, recalling that her aunts were married to one another as well. Sam had married Luna so that she could get the last name Loud just as Darcy had. Though in her case, Sam's parents weren't going to disown her or anything. Sam just loved both Luna and Lincoln and she wanted her name to be Loud as well so that everyone would know that she was part of the family.

"Oh yea…" Lincoln said, recalling that Luna had had feelings for Sam at the time. "You know, I do remember what she had told me about that."

"Well, what did she say?" Loan asked her father.

"Luna was actually already dating Sam at the time." Lincoln said. "And Luna actually kept it secret from Sam. She was ashamed that she had started to have sex dreams about me. Which eventually allowed me to take advantage of that situation. But that doesn't happen until later."

"That's correct. First let us go back to what happened to Luan…" Lisa said.

XXXXXX

"W-What happened to Aunt Luan a-after you…um…made sure she was broken?" Loan asked. She tried her best to not recall the video that Lisa had shown her.

"I called your father over so that he could see for himself the results of my experiment." Lisa said. "He was rather pleased with the results…"

After Lincoln and Leni had taken a shared shower (to conserve water), Lincoln made his way towards Lisa's bunker. She had sent him a text informing him that she was ready for him. Eager to see his new toy, Lincoln quickly finished on Lucy's still sleeping face ("Ew, dad!" Loan protested. "Really?" Lucy asked with a raised eyebrow. "That grosses you out?") and finished getting ready. Upon exiting the elevator to the second floor of Lisa's bunker, he found the young genius at her desk looking at the monitor.

"Greetings, elder brother." Lisa said as Lincoln approached her. She was typing away, finishing up a few things before she turned around to face him. "You will be pleased to know that I have succeeded in breaking Luan. She will no longer be a threat."

Lincoln nodded. "Good." He ruffled her hair affectionately and then smiled. "You did a good job, Lise."

Lisa blushed lightly. "Thank you, brother. I am glad you approve."

"Show me Luan. I want to see her for myself." Lincoln said.

Lisa then led him towards the elevator once more and they went to the final level of the bunker. Instead of going to the cell that Luan had occupied before, Lincoln was surprised to be led further inside. Past the cell, there was a closed door that led to a small room. It was a sparsely furnished bedroom and it looked like it was meant to house guests. There was a bed, a chair, and a small dresser. The room itself wasn't very big, just 8x10x10. And lying on the bed, staring up at the ceiling was Luan. The former comedian was pale, her eyes unfocused and devoid of any emotion, and she was dressed in just while panties.

Lincoln approached the bed and he took his sister's appearance in. Luan looked like shit, if he was honest. But also, she looked like a dementor had given her a kiss. Like her soul was no longer in her body, just an empty husk. He turned towards the young genius. "Is she aware that we're here?"

"No." Lisa said with a shake of her head. "Her mind is completely broken. For all intents and purposes, Luan is brain dead."

This shocked Lincoln. "W-What?"

"You asked me to break her. I have done so." Lisa stated. "As per Lori's orders, Luan is no longer a threat."

"But how am I gonna be able to use her?" Lincoln asked. And to emphasize his point, he lifted her right hand up and watched as it limply fell back onto the bed. "I can't fuck her like this!"

"That is a simple fix, brother." Lisa said, not bothered by his reaction. "Now that she's broken down, we can rebuild her with simple programming."

This gave Lincoln pause. "You're saying that you can program her?"

"I'm saying that I can make her the perfect toy." Lisa said.

Lincoln took a moment to consider what he had just heard. He still had a few days left before Lori checked up on their progress. If Luan could now be programmed then Lincoln would have his toy. He glanced down at Lisa. "How are we going to hide this from mom and dad?" He asked, a sudden thought entering his mind. "They're going to notice that something is up if she doesn't crack jokes anymore."

Lisa didn't look worried. "Fear not, brother. I can restore enough of her old personality that she won't arouse suspicion. After all, her mind is broken, it is not gone."

Lincoln shook his head. "Alright, I'll leave this up to you then, Lisa. I want to put her to the test in a couple of days, before Lori comes to see what we've done."

"What do you have in mind?" Lisa asked, curious.

"Oh…I just want to see if she really would do anything I ask of her, even if we have an audience." Lincoln said with a cruel smile.

Lisa wasn't sure what he had planned but it was obvious that his plan involved Luan's humiliation. "Very well, I'll have her ready by tomorrow night."

Lincoln then placed a hand on Lisa's head. "But before I go…there's something I want you to take care of."

Lisa wasn't surprised when she felt her brother's dick lightly smack her right cheek. "Of course, elder brother. Whatever you wish."

End of chapter.