A/N: Thank you for the three reviews I received on the first chapter! I'm used to getting...well...none, so thank you three so much! The only one of you three who asked a question was xXBoothxBonesXx, and you asked what the initials were. You got the Katherine Beckett, Richard Castle part, but the last half is Stana Katic, Nathan Fillion. Alright, on to the next chapter, then!

Disclaimer: I know I wish every night when I go to sleep that I could have this show, but the plot is all I have.

Chapter Two: This is the House that Doubt Built

"Okay, Mark, can you tell me where you were between midnight and three AM this morning?" Beckett asked, leaning forward toward her folder. Mark Irving, a handsome scruffy twenty-two year old, shifted in his seat.

"Can I ask what this is about?" he was the most polite murder suspect Beckett had in the interrogation room in a while, so she indulged him with little to no sarcasm.

"Your ex-girlfriend Luna was found dead this morning in her apartment," she replied, leaning back to gauge his reaction. She found that she could almost rule out suspects just by their initial reaction to hearing that one of their loved ones was dead. Mark was no exception. His slightly pink face lost all color and a tear fell from his eye before he could even blink. He looked shocked to find it on his cheek and wiped it away, his mouth open.

"I...I don't...this is a joke, right?" he looked to Castle, who shook his head. Mark clenched his jaw closed and sniffed, trying to contain his emotions in front of strangers. "What happened to her?"

Beckett's mind immediately transported her back to the crime scene, and she found herself swallowing back the bile that rose in her throat. She closed her eyes momentarily and steadied herself. "That's what we're trying to figure out," she answered. "So, where were you?"

"I was at home," Mark kept his eyes on Beckett's hands, "My roommate can attest. I was painting all night," he held out his hands for evidence. The lines of his hands were lined with red and orange paint, and Beckett found herself envisioning Luna's hands, dried and cracked with blood from the cuts that were sliced into the tender skin of her palm.

"What is your roommate's name?" she asked, blinking several times.

"Alex Kenny, he works at Saks," Mark said. "Look, do you have any idea who did this?"

"We should ask you the same thing," Castle replied. "Did Luna have any enemies, anyone who didn't get along with her?"

Mark bit his lip, running through his mental contact list. "Luna was loved all around. No one hated her. It was kind of hard to; she was such a happy person."

Beckett forced herself to pay attention and leaned forward. "So why did you two break up?"

Mark pursed his lips. Clearly this was not a subject he liked to dwell on. "She thought I was cheating on her with one of my friends from school, but I wasn't!" He held up his hands as if to surrender, to try to make them believe him. "She's my cousin, and we hadn't seen each other since we were kids, we hardly recognized each other. I tried to tell Luna that, but she was convinced. So I had planned for her to meet Olivia this weekend so she could tell Luna herself."

"Why didn't she believe you?" Castle asked. "Don't get me wrong, I know sometimes she can feel like there's no other alternative, but if she was such a happy person, why wouldn't she give you the benefit of the doubt?"

Mark shrugged. "That's what I asked her. I thought it was Minnie that was putting ideas in her head, but now I'll never know."

"Had Olivia ever met Luna before?" Beckett asked.

"She had seen her picture, but that's it," another tear fell from Mark's eyes and he wiped it off the table in embarrassment. "I had nothing to do with this," he said. "I loved her. I would do anything for her, and if I had been there when she was killed, I would have given my life so she could live."

Castle looked astonished. "That's a big statement to make," he noted.

"Haven't you ever felt like you found someone you couldn't live without?" Mark asked pleadingly. "Like you would die if something happened to them? Luna was that person for me. I would die for her in a heartbeat. She was the love of my life. She will always be the love of my life."

Castle, chagrined, glanced down at the table and over at Beckett's pale profile. She kept her eyes downcast and bit her lip, her eyelashes fluttering for a second in Castle's direction.

"Thank you for coming in, Mark. I'm so sorry for your loss," she said. She opened the door for him and let him out before her, shutting the door after him. "Well that was a bust," she rolled her eyes up to the ceiling and tried to shake off the nauseous feeling this case was giving her.

"He really loved her," Castle muttered.

Beckett narrowed her eyes at him from under her hand. "Yeah, so?"

"So, he said that he thought Minnie was the one putting those ideas of him cheating in her head. What if she was?"

"Castle, I interviewed Minnie, it's not her," Beckett replaced her hand over her eyes and returned to her seat. "She was devastated."

"I've seen killers act before," Castle pointed out. "But you're probably right." He sat in silence, tapping his chin with his finger, before groaning in frustration. "We've got nothing!"

Beckett looked vaguely amused. "Castle, we just started investigating. Did you want the killer to just drop by and say 'oh by the way, I totally did it!'?" She leaned forward and put her head on the cold table so she could hold her stomach without Castle seeing. "Because he's not."

"Are you still feeling sick?"

She sat in silence for almost a minute before she answered him. "I don't know what it is about this case, but I have a bad feeling about it. I just can't shake this horrible nauseous feeling," she closed her eyes and took a deep breath.

"Maybe you're pregnant," Castle chuckled. She sat up and fixed him with a glare, her mouth twisted upward in a kind of sick smirk. He looked sorry he said it the second he looked into her mortified eyes, and then the full realization of what he had just said hit him. He clenched his hands into fists. He had just suggested that she and Josh were having sex, and now he was picturing it and it was doing nothing good for his temper. He felt the inexplicable urge to punch himself.

"I wouldn't count on it, Castle," she retorted, standing up.

Castle, facing away from Beckett, looked hugely relieved. When she opened the interrogation room door and left, he jumped up and followed her. "What's our next move?"

"We go see Lanie," Beckett shimmied out of her jacket and draped it on the back of her chair, leaving her coffee behind on the desk. "See what she's got for us."

KBRCSKNFKBRCSKNF

"It was definitely rape," Lanie announced, drawing the sheet down to Luna's shoulders. Her face had been cleaned, though Beckett still looked pale. "Tearing of the vaginal wall, and traces of spermicide, so no semen, however, remember biology class in high school? When we had to dissect frogs and our teachers gave us dull razors to use to cut them open? Her cuts were made from the same kind, only it was sharp, extremely sharp."

Lanie took Luna's wrist and held up her hand. "See what I mean? If you look at her skin clean, you can't even see any of the slices. But, if you do this," she pushed Luna's fingers back just half an inch, "You can see all the little nicks he put in her flesh."

Beckett took a step backward and covered her mouth with the tips of her fingers again. Castle took a step forward, mostly to block Beckett's view of the body. "That is horrific," he commented. "I mean, cuts like that take a few seconds to hurt, but then the sting doesn't go away. And..."

"They keep bleeding," Lanie finished. "Also, he tied her to the bed with a generic three thread rope, and raped her first. Then, he cut her. I found traces of salt in the wounds, from her dried sweat. Then he poured scotch down her throat until her blood started thinning, causing the blood to flow faster from her cuts until she was on the verge of passing out and started vomiting. When she starting throwing up, he took her discarded underwear and tied them around her neck, so she drowned in her own vomit."

"I have to get out of here," Beckett launched herself away from the table and out the door, practically running out of the morgue.

Lanie watched her friend go. "What's wrong with her?"

"She's been feeling sick all day, but it didn't start until we got this case. The crime scene, the interrogation, now...she says she has a bad feeling about it."

"I don't blame her. This is pretty gruesome stuff," Lanie covered Luna's face with the sheet and leaned against the table. "A gunshot is one thing, but Beckett doesn't come in contact with a lot of sexual assault cases. I think being her, the big shot and the strong one around here; it's hard for her to understand being overpowered, like these women were. It makes her sick to think about."

Castle frowned. "And here I was, suggesting she was pregnant."

Lanie looked at him in exasperation. "Why would you suggest that?"

"I...I dunno..."

She smacked him in the chest with her gloved hand. "Unless you and her have had sex recently, don't even bring it up," she scolded. "Pregnant. Jesus, Castle, you would think you would know better."

"You would think..." Castle muttered. "I'm going to go find her."

"And knock her up?"

"No!"

"Then don't talk about it!"

KBRCSKNFKBRCSKNF

"Yeah, I was so mad, I mean, I told her to stay away from Jordan, but did she listen? Of course not! Yeah, I know. Anyway, I just got home, so I'll talk to you tomorrow, k? See you at eight. Bye."

"Welcome home, Elizabeth."

The pretty brunette turned on her heel and screamed. A gloved hand came up to cover her mouth. "Shhh, it's okay, it'll all be over soon enough."

Elizabeth squirmed and kicked against the man holding her, but he had no problem carrying her to her own bedroom, where each post of her bed already had rope tied to it. He slammed her down and connected her wrists and ankles. He placed duct tape over her mouth and kissed it, holding her chin roughly with his leather gloves.

Tears streamed from her eyes into her hair as she whimpered against the tape, pleading silently for the man to let her go. He wrenched her shirt open, sending buttons skittering across the floor, and she squeaked in surprise.

"It'll be just fine, Elizabeth, don't worry. Your pain will be over soon."

KBRCSKNFKBRCSKNF

Beckett leaned against the sink in the women's restroom, cradling her head in her hands, willing herself not to throw up. She heaved a sigh and looked into the mirror, into her reflection, and smoothed her hair. Her face was paler than usual, and she wrinkled her nose at herself, dissatisfied.

A tentative knock sounded at the door. "Beckett?" Castle's voice echoed throughout the bathroom. "Are you okay?"

She half-smiled and pulled the door open, causing him to almost topple over. "I'm fine, Castle."

He looked at her pale face and shaky hands. "You don't look fine," he noted.

"Yo," Esposito handed Beckett a manila folder. "We just looked into Mark, Minnie's, and Luna's financials, all clean. None of them had any reason to kill her."

Beckett didn't even glance at the papers, she just handed them back to Esposito. "I figured as much. So, why don't we go up to the university and see if she had any enemies or we can go to her job and find out of there were any customers that didn't like her or if there were any people who came in just to watch her. See if you find similarities."

"Similarities?" Ryan asked, coming to a stop behind Esposito.

"Look and see if there's a common person between the university and the job. I'm thinking this is more of a stalker than an enemy, so let's see what we can dig up."

"Beckett?" Montgomery leaned out of his office, his phone attached to his ear. "We've got another one."

Beckett turned to Castle, who looked apologetically at her, and as Ryan and Esposito took off toward their car, he placed a hand delicately on her back, just for a second, to let her know that if she needed him to, he would help her through it. She smiled up at him through a thin curtain of hair and grabbed her keys.

KBRCSKNFKBRCSKNF

It was the same man. Elizabeth Williams, aged 30, was lying dead in her own vomit, tied by each limb to her four-poster bed. Lanie determined time of death to be around two hours prior.

"Then how did we find the body so fast?" Beckett asked, keeping her back to Elizabeth's body.

Lanie almost smirked. "Your killer seems to have gotten a little sloppy. He didn't subdue your victim fast enough, because she got out a good few screams somewhere in the duration of his torture. He duct taped her mouth, but by the time he took it off to make her drink, she was still conscious enough to scream. And her neighbors were loud enough to call the cops. They thought she was watching a horror movie on loud."

"So she fought him. Any DNA under her fingernails?"

"She fought, but not that well. None that I can find so far," Lanie took off her gloves and grabbed Beckett's hand. "Are you sure you're going to be okay here?"

Beckett reclaimed her hand. "Castle told you?"

"You ran out of my morgue, girlfriend. I already figured," Lanie shrugged. "At least I didn't suggest you were pregnant."

Beckett blushed. "That was mortifying."

Lanie nodded. "Yeah, well, Castle looked as sick as you do at the thought of you and Motorcycle Boy, so I would cut him some slack."

Beckett glanced over at Castle, who was keeping his distance from the body while trying to glean some sort of insight, and looked back at Lanie. "He did?"

"Please, you think that man wants to think about you with anyone else but himself?" Lanie smirked. "He didn't think before he spoke, and that was his problem."

Beckett smiled. "Wouldn't be the first time."

"Yeah, yeah, get out of here, before you add more vomit to my crime scene," Lanie shooed her away.

"Lanie!" Beckett protested.

"Anything different?" Castle asked, joining Beckett's now solo conversation. She shook her head, noting now that Lanie had mentioned it, that Castle was avoiding her eyes, but still trying to be supportive.

"Nothing new, except she fought him a little more than Luna did," Beckett replied. "There's nothing else for us to get here, so let's go."

"Where to?" he asked.

"The precinct," she replied. "We would need to find a connection between these two vics, and we can't do that unless we talk to Mark or Minnie again and I don't think either of them are up for it today, excuse me," she added, dodging a passerby on the street.

"So, why don't you let me make you lunch at the loft?" Castle asked.

Beckett paused in the process of unlocking her car, and raised an eyebrow. "Is this an apology for asking if I was pregnant?" she asked.

Castle's face turned red. "Look...Beckett...I..."

"It's okay," she reassured him, sliding gracefully into her car. "I know you were just blurting out your normal slew of helpful insights. I'm not taking it too seriously or anything if that's what you're worried about."

Castle let out a sigh and leaned back in the passenger seat. "In that case...let me just buy you some Chinese food?"

"I'm not really hungry," she pointed out.

Castle gave her a chiding look. "You've been running around all morning and all you've had is coffee. You need to eat. TO CHINESE FOOD!" he shouted, pointing forward. Beckett turned on the car and turned to him, smirking.

"Please?" he asked, his hands in prayer position.

Beckett put the car in drive. "You're such a child."

"Chinese food, here we come! Pananananana pananananana!"

"Castle!"

"Sorry."