Meredith, Cristina and Alex were watching the end of the evening news with minor interest, more concerned with discussing Izzie than learning about Presidential approval ratings or the crime wave plaguing Seattle. "It had to be Sloan who made her so upset. He's such a dick," Alex scowled, shaking his head with displeasure.

Meredith frowned, her eyes shifting from the television to glance at the empty staircase in the hallway. "Maybe one of us should go check on her."

Cristina shrugged. "You can go. I don't work well with emotional basket cases."

"She's not an emotional basket case," Meredith admonished. "She's just…just…"

"An emotional basket case?"

Meredith glared warningly. "No, Cristina. Izzie's just…sensitive," she concluded hesitantly. "Whatever, someone needs to go make sure that she's okay. She's been up there for half an hour."

Alex and Cristina simply stared at Meredith expectantly. She sighed, rolling her eyes. "Fine, I'll go." She stood up, ignoring their simultaneous smirks as she left the living room.

She was halfway up the staircase when she heard a knock on the front door. She sighed, turning around and walking toward the entrance of the house. A look of displeasure crossed her face when she swung open the door, revealing a scowling Mark Sloan standing in the threshold. "Where's Izzie?" he demanded.

Meredith swallowed, holding up her chin defiantly. "She's crying in her room, which I'm assuming is your fault."

Mark rolled his eyes, pushing past her into the foyer. He halted when Cristina and Alex appeared before him, blocking his way to the staircase. "You should probably leave, Sloan," Alex warned, his eyes flashing with anger.

"This is between Izzie and me," Mark scowled, folding his arms across his chest. "You both need to get out of my way."

Cristina mimicked his motions, crossing her own arms as she looking down her nose at him. "I don't know what you did to Barbie, but you can't be here. We've made it a general rule not to allow penises in this house." Beside her, Alex cleared his throat, causing Cristina to roll her eyes. "Except for Evil Spawn's, of course."

Mark sighed. "I appreciate your concern for Izzie, but this whole thing is a misunderstanding. She thinks that I was with someone else, but…but I wasn't, and I need to fix this…I wouldn't be here if I didn't care about her."

Alex's face softened a bit, but Cristina remained motionless, her face still stern. "That's nice, but I don't really give a shit."

Again, Meredith glared at her. "I think we should stay out of this Cristina."

Cristina stared at her incredulously. "You're supposed to be my new lesbian soul sister. You're supposed to back me up here."

For the first time since entering the foyer, Alex looked away from Mark, his eyes shifting to focus on Cristina. "Meredith's right. This should stay between Izzie and Sloan."

She shook her head disappointedly. "You guys suck," she told them with a frown, but she moved out of the way nonetheless, stepping to the side so that Mark could move past her to the staircase.

He made it upstairs in record time, not even bothering to knock on the door when he came to Izzie's room. He opened it, his chest aching with guilt when he found her curled up in the fetal position, hugging her knees to her chest. She was fast asleep, wearing only an oversized Washington State University t-shirt and panties, her eyes swollen and her cheeks stained with tears. Mark sighed, shutting the door quietly behind him.

The click of the door shutting jolted Izzie from her slumber, and she sat up quickly, her eyes flying to the doorway as she stared at Mark with confusion. She blinked, her forehead furrowed at she watched him bewilderedly. "Mark, what're you…" Her eyes widened as she remembered the events of the past hour, and she sat up straighter, her face hardening. "You need to leave. I don't want you here."

Mark ignored her, walking to the bed and sitting on the corner of the mattress. He sighed with frustration when she backed away from him, scooting to the edge of the bed to put space between their bodies. "Izzie, you have to listen to me. You don't know what you saw-"

"I know exactly what I saw!" she snapped, her eyes flashing with irritation. "I saw your half-naked ex lover standing in your hotel room while you were showering in the bathroom."

"I didn't know Addison was coming to Seattle, Iz. She-"

"I couldn't care less whether you knew she was coming! What I care about is that you didn't respect me enough to stay away from her! That you slept with her knowing that I would be coming to your room later on! Did that thrill you, Mark? Did it excite you to think about screwing me on a bed that reeked of Addison Montgomery?"

"Izzie-"

"No, you know what, Mark? Just forget about it. This is my fault. I told myself repeatedly to stay away from you. I knew better than to get involved with someone like you…someone with so few sexual morals."

Mark's eyes narrowed irritably. He tried to remind himself that she was speaking out of anger, but she knew exactly how to push his buttons, and she'd done so with relative expertise. "Sexual morals? You want to talk to me about sexual morals?"

"What is that supposed to mean?"

"Apparently you've forgotten how this whole thing between us started, Izzie. Well let me refresh your memory. It all began with you sitting in my hotel getting wasted after your little boyfriend rejected you."

Her eyes narrowed. "What did you say to me?"

"You heard me, Izzie. I was sitting in the corner of the bar the whole time; I watched you. I watched you talking to George O'Malley, and I might not have been able to hear what was being said, but it doesn't take a genius to figure out what was going on between the two of you. No one looks at someone the way you were looking at O'Malley unless there's something going on. So cut the shit, Izzie. You don't have the right to talk to me about sexual morals when you're out fucking another woman's husband."

Her cheeks reddened, her eyes filling with tears as she looked away from his face. "You need to leave, Mark," she whispered venomously, standing up from the bed and walking to the other end of the room, gazing sightlessly out the window.

He pursed his lips, shaking his head as he retreated toward her. "I'm not leaving. You don't get to judge me for something you know nothing about. Addison was just-"

She spun around quickly, her eyes widening when she found him directly behind her, his face just inches from hers. "I don't want you here, Mark. I don't want you anywhere near me. I don't care what happened between you and Addison. There were no rules between us. You're free to be with whoever you want. So go…be free…you can screw all of Seattle for all I care."

He smiled bitterly. "You don't mean that. You do care, Izzie. You know you do."

"I do not! So get the hell out of my house, Mark!"

"I'm not leaving until we can talk like adults." She scowled, pushing past him, but he grabbed her wrist, pulling her body to his so that she was molded against him. "Stop trying to push me away," he demanded irritably.

Izzie stuck out her jaw defiantly, struggling against his chest, but the more she moved, the more aware she became of his arousal pressing hard against the pit of her belly. She swallowed, her angry eyes meeting his. "Leave."

His gaze remained unwavering. "No."

She fumed, struggling to breathe through her anger. She hated him at that moment. She hated him for blatantly hurting her by sleeping with Addison and by saying such hateful words regarding her and George, but most of all, she hated Mark because of his unfailing ability to make her want him. "You're a bastard," she seethed.

He grinned as he saw the lustful expression on her face. "And it kills you that you want me despite that."

She moved fast, her hand flying up with record speed to strike him hard across the cheek, but he caught her wrist just before her hand could connect with his skin. "Nice try," he gloated arrogantly, his lips crashing against hers an instant later.

She didn't fight him. For her, his bruising kiss was like a breath of oxygen for a drowning swimmer, and she moaned, moving her body so that her breasts caressed the strong muscles of his chest. "Christ, Izzie," he muttered, pulling the oversized t-shirt from her small frame, leaving her standing before him in only a pair of lacy hipster panties.

He took her plump bottom lip between his teeth, tugging on it ever so slightly as her hands worked quickly to unbutton the front of his jeans. He stepped out of them moments later when she'd worked the denim down his legs along with his cotton boxer briefs, and then he propelled her backwards, pinning her against the dresser.

She winced as the corner of the furniture bit into her lower back, and she retaliated, rising to her toes so that she could take his earlobe between his lips, sucking lightly before allowing her teeth to clamp down just hard enough to cause him to growl. His hands flew around her waist, bringing her body upwards and pushing her onto the dresser, ignoring the picture frame and candles that were knocked to the floor in her wake. His hands snaked into the waistband of her panties, and she lifted her hips, allowing him to edge the pink lace down her legs.

Mark dropped them carelessly to the floor, wrapping his hands around her thighs and pulling her hips to the edge of the dresser. Her eyes met his, staring unwaveringly at him as he thrust roughly inside of her. Izzie bit her bottom lip to stifle a moan, her head dropping backwards as sensation after sensation tore through her body.

She didn't even notice her head thumping against the mirror behind her as he propelled himself into her again and again. Her hips rose and fell in synch with his, and she reached up to hold onto to his waist. He caught her hands before they could connect with his skin, trapping her wrists inside his hands and urging them above her head.

His eyes rose from hers, connecting with his own in the reflection of the mirror. As he watched himself, his eyes darkened at the erotic image of his body moving over Izzie's, and he groaned, increasing his pace.

Izzie's mouth fell open as he drove into her with surprising force, and she closed her eyes in ecstasy, her body clenching around his moments later. Within seconds, Mark's own body tensed as he reached his peak, and then he was falling on top her, his forehead resting onto hers.

Izzie swallowed, opening her eyes as she struggled to regain her breath. As she listened to Mark's own ragged breathing, she couldn't help but mentally picture him with Addison, her mind conjuring up an image of him lying with her just so, his forehead resting against hers as he breathed heavily post-orgasm. The image made her feel dirty, dirty and used, and Izzie's face twisted as she struggled to keep her tears at bay. She brought her hands up, placing them against his chest and pushing him away with all the force she could muster. "I still hate you," she whispered heatedly, her voice laced with bitterness and hurt.

His eyes narrowed as he stepped away from her, and he shook his head angrily. "That's really nice, Izzie," he replied sarcastically, shaking his head disappointedly.

She adverted her eyes as he dressed quickly, allowing her own body to slide weakly from the dresser. Standing on trembling legs, she walked to her closet, covering her nudity with her robe.

Mark sighed, walking to her door and turning the knob. He paused before leaving, turning back and looking at her with a regretful expression. "I didn't sleep with Addison. I didn't kiss her…I didn't even touch her, Izzie. I wouldn't do that to you," he confided quietly, and then he walked out, pulling the door closed behind him.

He traveled quickly down the stairs, ignoring the curious looks of Izzie's roommates as he hurried toward the door.

"Mark-"

"Don't, Meredith," he snapped, racing toward the exit and slamming the door behind him.

Cristina raised her newly grown-in eyebrows at her roommates. "Well that was…interesting."

Alex nodded, his eyes traveling toward the stairs. "Okay, who's going to make sure she's okay?"

"I'll go," Meredith volunteered, already walking toward the steps.

Cristina shrugged. "Strangely, I actually care about what happened up there," she remarked, already hot on Meredith's heals.

Alex narrowed his eyes. "Well I'm not getting left behind," he muttered, moving quickly to catch up with his roommates.

The three of them glanced apprehensively at one another when they were standing outside of Izzie's bedroom. "Iz?" Meredith called out, knocking lightly on the door.

She was met with silence, so Cristina didn't hesitate to turn the knob, pushing the door open with ease. On the other side, they found Izzie sitting on her bed, clutching the shirt that Mark had left in her locker to her chest.

They walked slowly inside, noting curiously the fallen candles and picture frame that lay beside her dresser, and the abandoned panties lying next to them. Cristina smirked at Alex, but Meredith ignored them, walking quickly toward the bed and sitting down beside Izzie. "Iz, are you alright?"

Izzie sighed, trying to plaster a smile on her face as she nodded her head. "I'm fine."

Meredith bit her lip lightly, her expression displaying her disbelief regarding Izzie's statement. "Izzie-"

"No, seriously, I'm okay. Mark's…well, we're not good for each other, Mer. We…I think I'm better off without him. I don't want to get hurt again."

Meredith nodded sympathetically, pulling Izzie's hand into her own. "I understand," she said quietly. "But that doesn't mean that you don't want him anyway."

Izzie turned to look at her, her eyes wide as she met Meredith's in the dimly lit room. She nodded lightly, taking in a shaky breath as her head dropped to Meredith's shoulder, her long, blonde locks falling over her face.

And she cried.