Sheldon frowned at the screen of his laptop. He erased the last phrase he had written, huffing in frustration. He had never had such difficulty writing a contract before. When Penny had promised him she would sign whatever agreement he made, initially he was elated. The problem was that when he looked at his previous roommate agreement as a template, everything in it was either irrelevant or insufficient. The official apartment flag? It was still stuck to the side of his fridge, but he was certain that Penny would never give him reason to turn it upside down as a sign of distress. In fact, she diffused most of his panic whenever he felt overwhelmed. As for a zombie apocalypse or mime invasion? He had no doubt that she was fully capable of protecting not only herself, but everyone she cared about, and would do so to her last breath. He had considered a including a prohibition against whistling, but that minor clause was hardly worth creating an entire contract. Besides, he had a feeling that Penny would just deal with most minor disagreements they had by kissing him until he could barely remember what they had been arguing about. It was a sneaky, unfair way of dealing with conflict, particularly because it was so effective.

Naturally, his chief concern was his son, but in this, as in every other area he could think of, he was sure Penny was capable of surpassing any expectations he might put down on paper. The truth was that he felt any requirements he might ask of her would be more restrictive than beneficial. Several months ago, he had attempted to abandon Caleb to her care. While it was a cowardly thing to do, he knew he never would have attempted it if he didn't have complete confidence in her. So that was the crux of the matter: in every area that he could think of, a contractual relationship agreement would only be detrimental. With a sigh, he closed his laptop. He might get back to the agreement some other time, but he doubted it.

The next evening after dinner, Penny cautiously asked about the contract. "It's not that I want to slog through two hundred pages of legalese," she said with a laugh. "But I know how much you like drawing up contracts and stamping them with your little stamp."

"Notarizing them, Penny. I am an official notary public in the state of California. However, I haven't made much progress in writing a contract. I encountered an unusual dilemma."

"You had a problem writing up a contract? That doesn't sound like you."

"Unlikely as it sounds, it's true. In every circumstance I could imagine, I believe you would surpass any requirement I might have of you, making a contract completely irrelevant."

"Ooh, careful, Dr. Cooper. That sounds like another compliment. If you don't watch out, you're gonna make that a habit," she said. He was certain from her smile that she was teasing him, but it didn't matter as she leaned in and kissed him. His palms began to sweat as their embrace became more passionate. She had no problems sliding her hands up under the hem of his shirts. Feeling her caress against his bare skin caused unfamiliar desires to rise up within him. He wanted to touch her the same way, and yet it must be admitted he was scared to do so. He felt himself balanced on the edge of a precipice, afraid of the fall and knowing he wouldn't be the same person who picked himself up at the bottom of the slope.

Reluctantly, he pulled away, and she let him go with a sound that was half pleased murmur and half disappointed sigh. After a moment, she put a hand in her pocket. "I asked about the contract because I have something I was going to give you, after I signed it. It's sort of for you, but it's really for me…" She winced. "I'm not explaining it very well. Here." She pulled her hand out of her pocket and deposited a silvery ring into his palm.

He examined it carefully. "It's a claddagh ring. Why are you giving it to me?"

Penny looked blank. "A what ring?"

"Claddagh, named for the village in Ireland in which this symbol of joined hands, heart and crown are said to originate. The traditional symbolism of the ring indicates the wearer's relationship status." He peered closely at her face, trying to decipher the expression on her face. "Are you telling me you wish to alter the status of our relationship?" He wasn't sure that was her intent, since she seemed ignorant of the ring's meaning.

"Uh, no… I mean, sort of." She plucked the ring from his hand and turned it around in her fingers. "When I was in high school, it was sort of a fad for couples that were serious about each other. We called them promise rings. I knew a lot of girls who considered it a pre-engagement ring." What she didn't mention was that she used to think it was a stupid idea. But there was a whole lot she was willing to do for her whackadoodle boyfriend. Wearing a ring on her left hand was part of it, a small step closer to the commitment he wanted.

He laughed at that, the breathy little sound that indicated he was amused. "Since an engagement is considered to be a statement of a couple's intention to wed, a promise ring is entirely redundant."

She closed her fist over the ring. "It was a silly idea. Forget I even brought it up."

He quickly covered her hands with his. "It's an excellent idea, given our current circumstances. I would very much like you to wear it." His gaze flicked uncertainly down to their clasped hands. "Shall I put it on you?"

"No, no, that's fine. No need for that," she said quickly. She slid the ring onto her fourth finger. "I guess that means I'm taken now."

"Thank you. This means a great deal to me," he said seriously.

"Good," she said with a grin as she planted a knee next to his hips, settling into his lap.

"What are you doing?" he asked nervously as her whole torso came into torturously close contact with his. He sucked in a breath sharply as she rubbed her body against his.

"Making out with my more-than-just-a-boyfriend," she answered.

He groaned as she wrapped herself around him, no longer able to deny that he was attracted to her on a very basic, primitive level. In fact, he didn't even see the point in trying. He loved her, and when he was ready, he was going to make love to her and hold her in his arms all through the night… and he was starting to like the idea.

"I just don't get it. I mean, I thought this was what she wanted," Leonard complained.

Penny tried not to roll her eyes. This was the first time in months all their friends had gotten together. Now that Caleb was a little older, they could trust him to play by himself for a few minutes at a time without getting into something he shouldn't. So she had persuaded Sheldon to have their friends over for pizza so they could hang out like they used to. Unfortunately, Leonard had been monopolizing the conversation for several minutes with his fake engagement woes.

"Maybe Mandy just wants to focus on getting her degree," Bernadette said. "Before I met Howie, I didn't think I had time for dating either." She reached out and laced her fingers through Howard's, and he grinned back at her. Penny thought the two of them made the most unlikely couple. Apart from their height, they seemed to have little in common, but apparently, they had bonded over the fact that they both had overbearing parents. Although she couldn't quite believe it, Bernie seemed crazy about Howard.

She glanced over at Sheldon, sitting in his favorite spot on the leather couch. He was focused on watching Caleb, who was playing on the floor, happily crashing two of his toy trains together.

"But I thought this was just a pretend engagement so you both wouldn't get expelled or something," Penny said in confusion.

"Don't be silly; Mandy might be expelled, but Leonard would be fired," Sheldon chimed in absently, still watching his son.

She rolled her eyes at him. "Seriously, Leonard, why are you getting all worked up?"

"Because we're dating," he whined. "She could at least act excited. She says she's not even going to tell her parents."

Penny leaned forward. "How could she possibly be happy about the fact that you bought a ring at a pawn shop and told her the engagement wasn't for real? If you actually care for her, then you have to make her think she's the most important person in the world to you. I mean, look at you - you didn't even bring her with you tonight. Make her feel like you would crawl over broken glass and hot lava for her, not just toss some ring at her in order to save your own ass."

Leonard frowned and shook his head. "I don't know how."

"If you're sure she's the one, then I think you need a do-over. Buy her a real ring at a jewelry store. Plan something romantic for the proposal and put some effort into it."

Leonard still looked unconvinced, but Penny no longer cared. "Hey, speaking of plans…" She jumped up and grabbed something from her purse. "Caleb's birthday is in less than two months, and we could use some help. I just found these at a pharmacy today, and I thought they were perfect." She flourished a pack of party invitations with cartoon trains. "See? Now all the parents from his therapy group won't have to guess what to get him."

"Ooh, a party with twenty screaming toddlers, that sounds fun," Bernie said waspishly.

Penny shot her an exasperated look.

"Caleb is not having a birthday party," Sheldon declared sternly.

Her face fell. "What do you mean? It's his birthday. We have to celebrate it."

"Birthdays are nothing more than a license for a group of children to torment one of their peers under the guise of fun," he said adamantly. "I'm not allowing that to happen to my son."

"We'd just invite the kids from speech therapy. He already knows them all and usually gets along with them," Penny objected.

"Oh, you don't want to go there with Sheldon. He hates birthdays," Leonard said.

Penny looked over at her boyfriend, ready to dig in her heels and insist on a party for Caleb. Then she noticed his tense posture and the way he wasn't making eye contact with anyone. She laced her fingers through his. "This isn't about Caleb, is it?" she asked gently. "You had a bad experience as a kid, and that's why you hate birthdays."

"Not just one birthday: every birthday," he said. "I have a twin sister, remember? At every single birthday party I ever had, I was tormented by Missy and a cadre of friends just like her."

Her mouth twisted in sympathy, and she glanced around at their friends. She almost wished she hadn't prodded. Every time he revealed something about his past, all she heard were painful memories. It was no wonder he was always so tense and wary of people. Leaning in close, she whispered, "Do you remember what you told me about writing up a relationship contract?"

"Of course I do. I have an-"

"Eidetic memory. Yup, I know. But you said you trusted me more than any contract, right? So trust me now. I'll make sure Caleb has a great party, and I promise it won't be like when you were a kid."

He reached out and rubbed his thumb over the claddagh ring she wore. After a long pause, he nodded. "Okay… but we're not having it here," he added quickly.

"Wouldn't dream of it," she answered with a wry chuckle. "Okay, so the birthday party's back on," she said, raising her voice so everyone could hear her. "We'll probably have it at one of those kiddie play places, but you're all welcome to be there."

A stunned silence met her announcement. "What?" she asked innocently.

Howard was the first to recover from his surprise. "Just trying to get used to Sheldon 2.0," he answered, shaking his head.