A/N: I didn't write this story as a chaptered story, I wrote it all as one doc with multiple scenes. Instead of trying to post approximately the same number of words per chapter, I'm just going to post each scene as a chapter, which will mean some will be shorter and some will be longer. This is a slightly shorter chapter, so I'm going to bump up my posting timetable and post the next chapter next week, so you don't have to wait as long for Sterek stuff. :)

Also, if anyone is interested, I'm working on a new series of oneshots which involve Stiles and Derek texting each other, because I love the idea of them communicating like that for some reason. There are two stories posted already, and I have a third one written and it's just awaiting approval by my beta. So keep an eye out for that to be posted hopefully tomorrow.

"Stiles, sweetie, I really need to get up now."

Stiles mumbled a little in his sleep, throwing his leg over Lydia's thighs to join the arm slung across her rib cage. She looked down at him in affectionate amusement, pushing his arm off of her and wiggling her hips to try to dislodge his leg. "Mmm," he groaned happily, snuggling deeper into her side.

She was less amused by now. "Stiles Stilinski!" she whispered sharply. "Get off of me! I have to go to the bathroom."

He opened one eye, squinting up at her exasperated face. "You can hold it another few minutes, can't you?"

"I could, but then I'd probably end up with a bacterial infection in my urinary tract and that would mean a round of antibiotics. Also, several days without sex." She gave him a pointed stare and he promptly withdrew his leg, allowing her to scoot off the bed and head for his bathroom.

She was careful to tread lightly both on her way out and coming back in, but she accidentally hooked her toe in his hastily-discarded shirt from the previous night and tripped, slamming her hip into his dresser and shaking it.

"Jeez, Lyds, be a little quieter, would you?"

Lydia gave him a death glare. "Thanks for your concern. My hip is fine, how nice of you to ask."

"I just don't want my dad to hear you," he protested guiltily.

She rolled her eyes at him. "Stiles. I've been here practically every night for the whole summer. We're clearly not studying. I'm pretty sure your dad has figured out by now that I'm sleeping with you."

Stiles winced. "Could you not talk so casually about my dad being aware of my sex life?" he grumbled. "It's creepy. Parents should not know their kids are having sex. Actually, they probably should, if they're good and involved parents, which my dad definitely is. But he still should absolutely not know about my sex life."

"Just be grateful he never knew about Derek," she pointed out, but when his face fell, she bit her lip. It had been more than three months since Stiles broke it off with Derek, and it was a wound that had yet to heal. It was made even more painful when Derek left to go visit Cora and hadn't returned. She knew he was wondering if he'd ever see the wolf again, and mentally flogging himself for hurting him the way he had. Being the sweet boyfriend he was he had never mentioned how much it hurt him, too, but Lydia knew him too well to pretend it hadn't.

"Yeah, that's a conversation I really didn't want to have," he replied, his tone light in order to alleviate the tension in the room brought about by her careless mention of the name that they'd tacitly agreed not to speak. "He would have wanted to do the whole labeling thing. 'I don't understand, son. Are you gay? What about the Martin girl? Were you experimenting? You're not doing drugs, too, are you?' All sorts of roads I didn't want to go down."

Lydia laid a hand on his arm. "I'm sorry," she said quietly, and he shook his head.

"I can't pretend it never happened," he said with a shrug, but she could see the struggle to act indifferent. "We were a thing. And then we weren't."

"Because of me," she said bluntly. They'd never addressed the fact that their relationship had caused him to end one he didn't actually want to end. There had obviously been no question in his mind that it was the right decision, at least at the time, but she despised the fact that she'd inadvertently been the one to instigate that kind of pain. She never wanted to hurt him.

"It was my choice, Lydia," Stiles argued, sighing.

"I wish you didn't have to," she murmured. "I wish you hadn't had to choose between us."

He blinked at her, his expression turning wary. "What are you talking about? Of course I had to choose."

The casually spoken statement sparked an idea in her brain. More to the point, it reignited an idea she'd had awhile back but discarded as being too bizarre. It was worth a shot, though. She hated seeing him so unhappy, and if she could make things better for him she wouldn't hesitate to do whatever it took. "What if you didn't, though?" she asked slowly. "What would you think if I told you I didn't expect you to choose between us?"

"I'd think I'm the world's biggest superstud, because I apparently literally fucked your brains out last night," he said sarcastically. "You're crazy, Lyds."

She leveled an equally sarcastic smirk at him. "No, I'm a genius," she retorted. "You're not happy without him. I can see that. If anyone else had known about the two of you, they would be seeing it too."

Stiles shook his head. "I'm incredibly happy. We're together. It's all I ever wanted, and I have it. I have you. I couldn't be happier."

"Us being together was all you ever wanted, until you realized what it was like to have Derek in your life, too," she argued. "Yes, you're happy with me. But you're miserable without him. Or are you going to try to deny it?" she challenged him, crossing her arms over her chest.

He opened his mouth as if to object, then shook his head. "I'm not going to lie to you. Of course I miss him. Every day. But I couldn't be with him and you too, so I chose you. I can't believe you're arguing with me about this."

"I'm arguing with you because you're a dumbass. You can be with him, and me too."

"You want me to cheat on you with Derek?" he asked incredulously, forgetting in his surprise to keep his voice down.

She widened her eyes and tilted her head, indicating the floor below them where they could hear the Sheriff moving around. Stiles fell silent for a few moments, and then the Sheriff hollered up the stairs. "Stiles, I'm heading in to work! I'll see you this evening!" Stiles opened his mouth to yell out a reply when his dad continued. "Good morning, Lydia! I'll pretend you weren't here if you'll make sure he washes his sheets!"

He flinched dramatically as Lydia giggled and opened the door. "Sure thing, Sheriff!" she called back down. They waited until the door slammed shut behind him before she moved back to the bed and they resumed their conversation. "To answer your question, no, I don't want you to cheat on me. Nor do I want you to cheat on him. I propose we share you."

Stiles' mouth fell open in shock. "You what? Do you mean like a time share? You each get your turn with me? Will we have to schedule all of this in advance? Like divorced parents. You get me during the summer and every other weekend during the school year, and he gets me during the week?"

She rolled her eyes, grinning. "No, sweetie. I mean share you. As in, the three of us together." She bit her lip again, wondering if her idea was pushing Stiles further than he was willing to go.

Desire flashed in his eyes and she smiled triumphantly. No matter what he said from this point on, she knew she would win the fight. He'd telegraphed how much the idea appealed to him and that was all she needed to know. "He'd kill me for bringing the idea up," he said finally, reluctantly. "Hell, he'd probably kill me for daring to speak to him again. And that's assuming I ever will speak to him again."

"I think you underestimate how much he cared about you, Stiles," she sighed impatiently. "You don't leave town over disappointment or hurt feelings. You leave town because your heart is broken and you can't stand the idea of seeing the person who broke it."

He gaped at her. "You can't possibly be serious," he objected. "I'm pretty sure Derek Hale is incapable of loving anyone. He cared about me, maybe, but love? No way."

"You're an idiot," she muttered. "You had to be told I wanted you when it was right in front of your face for months. Maybe it was right in front of your face with Derek, too, and you just never saw it because you didn't believe it was possible. Maybe he was trying to tell you all along."

"I love you, Lydia, but you're wrong. Derek didn't love me. Besides, when did you become his champion? Why is this so important to you?"

"Because you're important to me, you moron!" she fumed. "Although right now you're being so impossibly pig-headedly stubborn that I don't even know why I bother!"

"Because you love me?" he ventured, giving her his most charming smile. She shook her head and lifted her eyes to the ceiling as if asking for divine guidance, or possibly intervention.

"I do. And I'm certain Derek did too, even if you refuse to believe it. It can't hurt to just ask him. Will you be in any worse a position if you ask and he says no, than you're in right now?"

"Yes. Because he'll throw me out on my ass, which is very narrow and can't withstand that kind of abuse."

Her eyes sparkled and she grinned wickedly. "I have it on good authority that your ass can take quite a pounding," she murmured, her tone provocative. "And that is something I would love to see."

Stiles swallowed with extreme difficulty, nodding his head in an erratic, bobbing motion. "Sure. I'll go ask him. Right now."

Lydia laughed in delight. "We have to find him and make him come home, first. Then we can make him an offer he can't refuse."