"Change is the law of life. And those who look only to the past or present are certain to miss the future."

-John F. Kennedy

Penny breezed past the entrance and headed over to Sheldon's office in the university. It was almost noon and she had been looking forward to being able to talk to him one-on-one after last night. She had to give him credit. If she was punched so hard in the head, she wouldn't have gone back to work the next day. Sheldon was a strong man and he had things to do. Although she would have preferred him to stay at home and rest, she admired him for that.

She found herself standing in front of Sheldon's door and knocked on it softly. On the other side, Sheldon called out for her to come in and so she pushed the door open. He was sitting on his desk, his eyes glued to his laptop as he typed away. He tilted his head up to meet Penny's gaze before saving the document he drew up and closing his laptop. "Hello, Penny. I am very impressed with your punctuality. It is something that I have not noticed before. Kudos."

"Thank you," Penny responded as she took a seat on one of Sheldon's chairs in front of him. "So, how you been?"

"Well, my existence is a continuum, so I've been what I am at each point in the implied time period," Sheldon answered with a cheeky grin, causing Penny to giggle. "Bazinga. To answer your question truthfully, although what I did say prior to this is also the truth, I am doing well. What about you?"

"Oh, I'm great. I have a shift later and I'm going to pick up my new script after work. I'm gonna be exhausted but it's life." Penny was really didn't enjoy being a waitress anymore and she wished that her upcoming role would open more doors for her. "Sheldon, are you sure you're fine?"

"I am," Sheldon replied with a nod. "What makes you think I'm not?"

Penny gulped. "Well, it's just that you remember everything, according to the boys. You're acting different and make it look like it's not a big deal. Every time we hang out, you're always getting these memories and seem so excited after remembering them. You get them all back and you don't look affected about it."

"I understand your confusion. Let me begin answering that with a question. Do you know what homeostasis is?" Sheldon asked as he put his hands together and placed it on top of the desk. Penny shook her head, so he decided to tell her about it. "Homeostasis refers to a system's ability to regulate its internal environment and maintain a constant condition of properties like temperature or pH."

He was met with a strange look from Penny. "Change, Penny. I do not like change and I rather have things be the way they usually are."

"So you mean you're going to change into the same man you were before losing your memory?"

"Not change into, but revert back to. Penny, I enjoy having your company during the past weeks. I hope you do not take it personally and leave the group. I will not think anything less of you now that I am back to my old self."

Penny reached out and grabbed his hands, only to pull away when he twitched. She watched him as he opened his desk drawer and pumped a good amount of hand sanitizer on his palm. As he rubbed the sanitizer in, Penny sighed. "You don't like germs, do you?"

"It's intolerable. Do you know what kind of diseases you are vulnerable to when touching other people?"

It made Penny's heart sink. "What about your friends? A big deal about your memory loss was whether or not you could trust them after knowing what they did to you."

"I admit that was a concern but now that I remember everything, I find that I need them in my life to continue prospering in this world. For example, I need them to drive me to work or to the comic store."

"So basically you're using them to help yourself?"

"No, but to think of it another way, I am using them as tools."

Penny scoffed. This wasn't the Sheldon she knew. The Sheldon before last night wouldn't say such thing. She abruptly stood up and headed to towards the door. She heard Sheldon's voice one more time. "Where are you going?"

"I'm just going to get some air. I'll be back," Penny said before leaving his office. She didn't see him following right behind her but she continued walking down the hallway. As she went outside of the university, Penny couldn't help but think about how different Sheldon acted towards her. He seemed like an entirely different man. The warm feeling she had whenever she's around Sheldon was replaced with a much colder and somehow harsher aura.

Penny forgot her jacket inside Sheldon's room and she didn't realize how chilly it was until now. She wrapped herself with her arms and sauntered to the open park bench in front of a nearby garden. She lowered herself down on the wooden seat and noticed the patch of California poppies yet to bloom. Penny had been in Pasadena for about two months and she had never encounter the beautiful plants and flowers indigenous to southern California. Her eyes had only been focused on capturing her dream and she hadn't paused for a moment to think about where she really was. She had been to the west twice for when she visited Disneyland, but those were the only times she had visited the state.

It was relieving for her to not having to endure the endless winter nights in Nebraska anymore. Penny was done with the cold and ready to move into a much warmer climate. True she missed all her family and friends back home, but her life in California was filled with the unknown and excitement. The clouds began to move away in front of the sun and Penny took in the relaxing ray of light. She closed her eyes shut as she thought about the other things that were good in her life.

"Penny," a small shallow voice caught her attention and she quickly reopened her eyes and looked around. She found Sheldon with his hands clasped behind his back, wearing his blue windbreaker to keep himself warm. He slowly approached her with caution until he took a seat right beside her on the bench. Penny noticed that he was holding her leather jacket she left back inside in his hands. He handed the jacket to her and she smiled softly at him. "I do not appreciate you running away from me like that."

"Sorry," she responded with sincerity. Penny felt awful for leaving him so suddenly, but she needed to have her mind cleared.

"Was there something that I have mistakenly said that upset you?" Sheldon asked.

She wasn't sure if she should tell him what was really on her mind, afraid of scaring him away. "It's just that- well, you've been..."

Penny was having trouble putting her words in the nicest way as possible. "You don't seem to be the Sheldon I knew."

"What makes you reach that thought?"

She could only shrug for a moment. "It's unlike you to call people 'tools.' That was really rude and insensitive. You shouldn't really be calling anyone that way."

Sheldon's face right then was comparable to a child's expression after being scolded. It was rather innocent and understanding. "Okay. If I may add, I did not say those words in order to insult someone." It was quiet, and Penny was hated these awkward pauses. Sheldon, however, finally had a chance to speak. "Penny, I also understand what you were concerned about back in my office. Change is always something I am not comfortable about. For example, I was unhappy by the recasting choice of the recent Star Trek movie. Zachary Quinto as the new Spock caused distress and it upset me even more when I was mailed a cardboard cutout of Zachary Quinto instead of Leonard Nimoy."

"But did you like the change though?"

He sighed. "Although I had my doubts about whether or not Zachary Quinto will be able to top Leonard Nimoy's performance, it had some of its merits. Zachary Quinto was a weird, wonderful, unrepeatable event."

"What's so different about this time?"

"Penny, ever since I regained all my memories, I needed to resume my normal life which included schedules and routines. Those were what made me me. If I choose to ignore them, it would cause a state of chaos. Too many disruptions in my life make me feel uneasy."

She didn't even think about her next question. It sort of slipped out by accident and without second thought. "Am I a disruption to your life?"

He stared at her with wide-opened eyes. "Why do you ask such a question?"

"Well, it's because you met me after you lost your memories. Now that they're back, you'll realize that I was never incorporated into your life before the accident. You might not have time to hang out with me anymore."

Sheldon had the urge to wrap his left arm around her shoulder and pat it gently to comfort her, but the thought of germs made him squirm. Yet, he was able to push it away and challenged his fear of germs by doing what he wanted to do. At first, she could feel him tensed and gradually become more relaxed until he was leaning into her side slightly. "There, there. Penny, you are important in my life. I do wish to have your presence with me as I continue to get back into my usual ways."

She sniffled and he pulled back. Penny gave him another smile before turning around and digging through her purse. She retrieved a small neatly-wrapped box and presented it to Sheldon. "I was going to give you your birthday gift last night but I forgot all about it."

He glanced down to the gift in the palm of her hands and then to Penny's green eyes. "Penny, you didn't give me a gift, you have given me an obligation. I must now give you something of equal value based upon on your present and your perceived level of friendship."

And there it was. Raj had warned Penny about his viewings in giving gifts. "You don't have to get me anything in return, sweetie."

Sheldon held her gift in his hands and slowly unwrapped it, opening the box afterwards. He gasped and awed at what was inside. "Wow! An antique Vintage Marx Union Pacific M10005 Tin Train Car." He lightly grazed his fingertips across the packaging of the small train as he admired it. The train car reminded him of the time Penny took him to Carney's after he got stuck on a problem during work. It was the day he revealed his true feelings to someone for the first time, something he had thought he was better than to do. In reality, he was just afraid of the outcomes that were possible.

He hugged her and he felt a tear run down Penny's cheek and onto his windbreaker. Sheldon held her close for three seconds before pulling away and not giving into the urge to run home and take a shower. "Thank you, Penny. This was very thoughtful."

"I wanted you to remember all the fun times we shared ever since we've met," she responded.

"Penny," Sheldon began, still clutching her gift in his hand, "I'll never forget them. If I were not born with an eidetic memory, I still promise to never forget them."

She leaned into his cheek and pressed her soft lips on it. "I know you won't."

A/N:

A pure Shenny-filled scene for all of you! Seriously, I can't get enough of these two. I've written the next six and all it needs is another look through. To all you readers, I love you guys and I thank you for taking the time to read this and giving a review. It makes my day!

Coming up: Sheldon gets a visit from Amy, and another discussion between him and Penny.